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Fri Aug 28th, 2026 @ 1:48pm

Lieutenant Xey

Name Xey

Position Chief Science Officer

Rank Lieutenant


Character Information

Gender Agendered/Non-Binary
Species Trill Symbiont inhabiting a Trill Host - Legally and medically, Xey remains classified as a Joined Trill, although this classification is controversial on Trill.
Place of Birth Mak'ala, Trill
Age Current Host Body: 30 / Xey Symbiont: Approximately 180 years old
Date of Birth Tarin Rel: 12 February 2361 - Xey's precise emergence date is recorded by the Trill Symbiosis Commission but is rarely used as a personal birthday.

Physical Appearance

Height 5ft 9ins
Weight 12st 5lbs
Hair Color Dark brown
Eye Color Hazel
Physical Description Xey inhabits the body of Tarin Rel, a thirty-year-old male Trill of average height with a lean, athletic build developed during years of flight training and Starfleet physical conditioning. They have short dark-brown hair, hazel eyes, and the characteristic Trill spotting that begins at their temples and descends along both sides of their body.

Their features are fine rather than rugged, with a narrow jaw, prominent cheekbones, and an expressive mouth that tends naturally toward a smile.

Before their accident, Tarin was known for controlled, methodical movements. Years spent pursuing flight control reinforced a tendency toward precision. Their posture was disciplined, Their gestures economical, and even mundane actions tended to be performed with the careful coordination of someone accustomed to operating complex machinery.

Xey moves differently.

The difference is subtle enough that someone meeting them for the first time would probably never notice. Those who knew Tarin before the accident often do.

Xey's movements are more instinctual.

They tend to act first and allow their body to follow without consciously considering every movement. Their gestures are spontaneous, Their expressions more animated, and their posture considerably less formal than Tarin's had been. They will lean against consoles, gesture broadly while speaking, turn quickly toward an unexpected sound, or reach for something without appearing to calculate their motion beforehand.

There is an almost unconscious fluidity to them.

This is particularly interesting because Xey is, in a literal sense, operating a body that was never originally theirs.

Rather than producing awkwardness, however, the years of neurological integration between host and symbiont have made control increasingly intuitive. Xey does not normally think about making Tarin's hand move any more than an ordinary humanoid thinks about moving their own.

Sometimes the body simply acts.

Xey takes considerable pleasure in this.

They occasionally pause afterward to appreciate physical sensations most people take for granted: warmth from sunlight, cold air, the texture of fabric, the flavor of food, or the simple sensation of walking barefoot across grass.

This is not because Xey lacks experience with physical existence. Quite the opposite. They remember five previous bodies in extraordinary detail.

Their body, however, is different.

It is male. It is young. It is healthy. And unlike every previous host, there is no second consciousness sharing it.

Xey maintains Tarin's excellent physical condition and continues many of their old exercise routines, particularly swimming, climbing, and cardiovascular training. They consider maintaining the body a responsibility as much as a pleasure.

There is no external indication that Tarin Rel is neurologically dead.

To casual observers, Xey appears to be an ordinary young Joined Trill.

Family

Spouse None
Children None
Mother Mera Rel - an administrator in the Trill planetary education system. She regards Tarin as dead. Although she intellectually understands that Xey did not kill her son and did everything possible to preserve him, she has considerable difficulty looking at Tarin's body while knowing that Tarin himself is gone. Contact between Mera and Xey is infrequent and painful for both of them.
Father Corin Rel - A structural engineer specializing in subterranean construction and geological stabilization. Corin has adopted a more clinical attitude toward Xey's condition than his wife, but that should not be mistaken for acceptance. He considers Xey a living person and bears the symbiont no hostility, but he cannot comfortably regard the person occupying their son's body as family. He and Xey exchange occasional correspondence.
Siblings One older sister, Lessa Rel. Lessa has adapted somewhat better than their parents. She refuses to call Xey Tarin, but unlike the rest of the family she occasionally speaks with him socially rather than out of obligation. Their relationship remains unusual. Lessa sometimes finds herself treating Xey like her younger brother before abruptly remembering that the person answering has memories extending more than a century before her birth. Xey considers her friendship one of the few surviving connections to Tarin's life that does not feel uncomfortable.
Other Family Xey possesses memories of five previous hosts and consequently remembers parents, siblings, partners, children, friends, colleagues, and descendants belonging to several different lifetimes. Trill cultural expectations discourage a symbiont from attempting to resume the relationships of previous hosts. Xey respects the principle. That does not make the memories emotionally meaningless. There are people alive on Trill whom Xey remembers holding as infants and who now know him only as an elderly relative's former symbiont. One of the peculiar cruelties of their current condition is that, for perhaps the first time, Xey has no true family of their own.

Personality & Traits

General Overview Xey is vivacious, curious, observant, stubborn, and intensely determined to enjoy being alive. One does not often need a tricorder or internal sensors to locate them; the sound of their laughter echoes down corridors. This quality has become considerably stronger since the accident.

Before Tarin's death, the joined personality of Tarin Xey was determined and disciplined. Tarin contributed ambition, competitiveness, precision, and a fascination with flight. Xey contributed a love for life, joy, humor, intellectual inquisitiveness, accumulated experience, and perspective developed through five previous lifetimes.

Their joining produced someone confident and energetic who believed an entire lifetime of joint adventure lay ahead.

That lifetime lasted only several years.

The accident changed Xey profoundly.

Xey does not regard their continued existence as shameful.

A large portion of Trill society does.

To traditionalists, the present arrangement is grotesque. Symbionts are not supposed to dominate their hosts. Joining exists to create something new through they union of two living minds. What exists now violates the philosophical foundation of Trill symbiosis.

Xey understands that argument.

They simply refuse to cease existing as themself because other people find their survival aesthetically or philosophically uncomfortable. If anything, the disgust directed toward them has produced a stubborn enthusiasm for living.

Xey eats good meals because they can taste them. They travel because they can still see new places. They laugh loudly. They attend concerts. They swim.. They dance without apology. They accept invitations. They try unfamiliar foods, They watch sunsets.

They have become almost aggressively appreciative of ordinary existence.

There is defiance in it.

Every pleasurable moment is, in some small fashion, Xey’s answer to those who believe their present life is an error that should merely be endured until the host body finally dies.

This does not mean Xey is perpetually cheerful; their condition troubles them enormously.

They know that Tarin is dead.

They remember being Tarin Xey. They remember Tarin's childhood because those memories had already been integrated during joining. They remember Tarin's parents, ambitions, insecurities, friendships, and dreams.

But remembering Tarin is not the same thing as being Tarin and that distinction matters deeply to Xey.

For that reason, they abandoned the name Tarin Xey following their recovery.

They use simply Xey.

Some interpreted the decision as callous. Xey regards it as respect for the dead.

Tarin Rel existed. Tarin Xey existed.

Neither exists anymore.

Pretending otherwise would make Xey’s current existence easier for other people at the expense of truth.

Xey is socially confident and generally friendly, though this has developed a sharp reaction to pity. Sympathy they can tolerate. Curiosity they welcome. Medical questions rarely offend them.

Being treated as a corpse, parasite, zombie, puppet, or medical curiosity does.

They possess the accumulated emotional memories of five women and the shorter shared experience of Tarin's male life. As a consequence, their perspective on gender is unusual even by Joined Trill standards.

Xey does not consider their previous female lives alien or separate.

They are their lives.

They remember pregnancy through one host. They remember motherhood through another. They remember being a daughter, sister, wife, widow, and grandmother.

They also remember Tarin's experience of becoming a man, his relationships with other men, his insecurities, and the peculiar novelty Xey experienced when their minds first combined.

Now Xey inhabits that male body without Tarin's personality accompanying them.

They find the experience fascinating, disorienting, and occasionally funny.

They do not treat it as a tragedy.

Xey has already had five opportunities to understand life through female hosts. They intend to learn as much as possible from this one.
Strengths & Weaknesses Strengths

Accumulated Experience: Xey possesses memories and practical knowledge derived from six host lives, although Tarin's memories cease at the moment of the accident.

Scientific Breadth: Several previous hosts worked in scientific or technical professions. Xey consequently possesses unusually broad interdisciplinary knowledge.

Xenobiology: Experienced with comparative life sciences, ecosystems, symbiotic organisms, and non-humanoid biology.

Exotic Particle Physics: Xey has developed expertise in unusual subatomic phenomena, high-energy particle interactions, exotic radiation, and particles or fields that fall outside ordinary models.

They are particularly interested in phenomena encountered during deep-space exploration that resist immediate classification.

Cognitive Science: Xey has developed a particular interest in consciousness, memory, neural integration, telepathy, and the biological basis of identity.

Some of their interests are obviously personal.

Sensor Interpretation: Excellent at recognizing unusual patterns in scientific sensor data, particularly when identifying phenomena whose signatures do not correspond neatly with known classifications.

Piloting: Xey retains Tarin Xey training as a Starfleet flight-control officer and remains fully qualified on shuttlecraft and many Federation starship systems.

They no longer consider piloting their primary profession.

Multitasking: A Trill symbiont's binary neurological structure is particularly well suited to integrating large quantities of information.

Long Perspective: Xey has witnessed political disputes, social trends, scientific theories, and personal crises repeat themselves in different forms across generations.

They are consequently difficult to panic.

Adaptability: Surviving six joinings—and one catastrophic neurological event—has made Xey unusually accepting of drastic change.

Emotional Resilience: Xey has experienced bereavement repeatedly across multiple lifetimes and possesses considerable perspective when coping with loss.

Curiosity: Xey is genuinely fascinated by unfamiliar phenomena and rarely dismisses something merely because it appears strange.

Social Confidence: Having lived many different social roles, Xey is comfortable speaking with senior officers, civilians, scientists, diplomats, and strangers.

Physical Coordination: Although Tarin's consciousness is gone, the body's learned motor pathways remain intact. Xey can access much of Tarin's procedural memory, including piloting reflexes, swimming, climbing, and basic combat training.

Interestingly, Xey uses those physical capabilities differently than Tarin did:

Tarin favored precision and consciously controlled movement.
Xey relies much more heavily upon instinct, reflex, and spontaneous action.

Trill Symbiont Memory: Xey possesses clear autobiographical memories from previous joined lives.

These memories are not simply stored records. Emotionally, they are remembered as events Xey personally experienced.

Weaknesses

Neurological Dependence: Damage or disruption to the neural pathways connecting Xey to the host brain could be catastrophic. Some attacks which might not so seriously harm others can place Xey into a life-threatening condition.

No Host Consciousness: A Joined Trill normally benefits from the interaction of two personalities. Xey no longer does. There is no second perspective to challenge assumptions, moderate impulses, or contribute new emotional insight.

Identity Isolation: Xey homeworld is filled with people who possess no accepted cultural category for what they have become. This can produce profound loneliness.

Social Stigma: Many Trill find Xey existence disturbing. Some consider him an abomination of symbiosis even while acknowledging that they committed no crime.

Host Family Estrangement: Tarin's relatives see their son's living body while knowing the person they loved is dead. Their grief remains a significant emotional burden for Xey.

Defensiveness: Xey reacts poorly to suggestions that their present life is less legitimate than that of another sentient being.

Risk-Taking Enjoyment: Their determination to experience life can occasionally become reckless.

Impulse Control: Xey has developed a pronounced dislike of postponing enjoyable experiences.

Fear of Confinement: Extended hospitalization, enforced isolation, or anything resembling indefinite medical observation causes considerable anxiety. Xey spent months after the accident being examined by physicians and Commission specialists. They have no desire to repeat the experience or anything like it.

Uneasy Relationship With Vulcan Telepathy: Xey does not blame Vulcans for what happened and intellectually understands that the dying officer acted in good faith. Nevertheless, they experience anxiety when participating in mind melds or similar telepathic procedures.

Loss of Tarin's Intuition: Xey retains much of Tarin's procedural knowledge but no longer possesses Tarin's living instincts or personality. They can remember how Tarin approached a problem but can't quite think the way Tarin did. This means Xey often arrives at the same physical result through a very different process. Tarin might have executed an action carefully and methodically. Xey is more likely to trust instinct and reflexes and simply act.

Institutional Scrutiny: Starfleet Medical and the Trill Symbiosis Commission continue to monitor Xey’s neurological condition closely.

Future Uncertainty: No one knows precisely what will happen when Tarin's body eventually dies. Xey is theoretically eligible for transfer into another host, but no comparable case exists. Xey privately fears that the Commission may reconsider that promise when the time actually comes.
Ambitions Xey's most immediate ambition is remarkably simple:

To have a good life.

They do not intend those words casually.

Xey wants friends. They wants meaningful work. They want to visit unfamiliar worlds, eat foods they have never tasted, learn useless skills, make embarrassing mistakes, fall in love if circumstances allow it, and someday look back upon their strange period of their existence without regarding it merely as an interval between legitimate hosts.

Professionally, Xey intends to become an excellent Starfleet scientist.

Their current interests increasingly center on exotic particle phenomena, consciousness, symbiosis, unusual forms of energy, and unconventional forms of intelligence.

They are particularly fascinated by phenomena that do not conform to established scientific expectations.

Xey would eventually like to lead a Starfleet scientific department or participate in long-duration exploratory missions.

They have not abandoned flight entirely and still enjoys piloting recreationally.

There is also a quieter ambition they rarely discusses.

When Tarin's body eventually dies, Xey hopes the Symbiosis Commission will permit another joining.

Not because they consider their present existence incomplete, but because Xey remembers what genuine joining felt like. They miss having another mind beside their own.
Hobbies & Interests Swimming
Shuttlecraft piloting
Stellar cartography
Xenobiology
Exotic particle physics
Observational astronomy
Live music
Dancing, despite only moderate talent
Trying unfamiliar foods
Cooking recipes remembered from previous hosts
Hiking
Planetary ecology
Theatre
Old aircraft and atmospheric flight
Travel
Museums
Board and strategy games
Collecting small objects from places they have visited
Photography
Learning activities their previous hosts never attempted but always intended to.

Xey has also developed a habit of keeping a private list entitled 'Things Worth Being Alive For'. Entries range from profound experiences to extremely trivial ones.
Languages Spoken Trill
Federation Standard
Vulcan, conversational
Basic Klingon
Some Tholian scientific terminology

Background Tarin Rel was born on Trill in 2361.

From childhood he was unusually ambitious. His academic performance was excellent, though not effortless. Tarin succeeded largely because he possessed the discipline to work harder than most of his peers.

He became interested in Joining as an adolescent.

Like many prospective hosts, Tarin understood that desire alone meant very little. The number of suitable hosts greatly exceeded the number of available symbionts, and candidates were expected to demonstrate intellectual ability, emotional stability, physical health, adaptability, and the capacity to contribute meaningful new experiences to a symbiont's future lives.

Tarin shaped much of his early adulthood around becoming worthy of selection.

He studied hard. He participated in athletics. He volunteered in community projects. He learned atmospheric flight. He traveled away from Trill.

He deliberately pursued experiences outside Their comfort zone because he believed a host should offer a symbiont something it had never possessed before.

That philosophy ultimately made him an unusually attractive candidate for Xey.

Xey had already lived through five female hosts.

The Commission considered a male candidate desirable because a host of a different sex would provide Xey with an entirely new category of embodied and social experience.

The joining occurred when Tarin was twenty-one. It was successful.

Tarin Xey emerged curious, energetic, and almost immediately fascinated by the experience of being male. Tarin already knew what being male felt like, of course. Xey did not.

Xey experienced Tarin's body not merely through sensory information but through the emotional context of someone who had grown within it. Tarin got to experience memories and context of several female lifetimes, and even their own male self from a new perspective.

The experience reinforced their interest in exploration.

Tarin Xey entered Starfleet Academy and specialized in flight control.

The combination proved highly successful. Tarin supplied precision, confidence, and enthusiasm for piloting, while Xey contributed experience, joy, and technical knowledge derived from previous hosts.

He graduated as a Conn officer.

For years, everything went according to plan.

Then came the accident.

During an away mission, a Vulcan Starfleet officer suffered catastrophic injuries. Medical evacuation would not arrive in time.

The Vulcan knew he was dying and they asked Tarin Xey to preserve his katra until it could be delivered safely to Vulcan.

There was no suitable Vulcan recipient available. Tarin Xey understood immediately why the request had been made.

To a Joined Trill, allowing a mind to perish when it might be preserved felt horrifyingly familiar.

Every Trill knew what happened when a host died before a symbiont could be removed and the analogy was impossible to ignore.

So Tarin Xey agreed.

The attempted transfer failed. Exactly why remains disputed. The interaction between Vulcan telepathy, Trill neurobiology, and Xey's existing neural integration produced an event none of the participants anticipated. Perhaps the Vulcan's extreme injuries contributed to the failure.

The Vulcan katra did not stabilize. Tarin's consciousness was catastrophically disrupted.

By the time medical personnel intervened, the personality and autonomous identity of Tarin Rel had been destroyed.

The Vulcan katra was also gone.

Only Xey survived. Xey, in an otherwise perfectly healthy host body.

Those two facts created an unprecedented problem.

Ordinarily, a symbiont influences a host through extensive neural integration while the host brain remains an active partner.

Tarin's brain was still biologically functional. Their autonomic systems operated. Their sensory structures remained intact. Their motor cortex could still control the body. Large portions of motor memory and learned physical behavior remained neurologically encoded.

What no longer existed was Tarin.

The symbiont remained fully conscious, and it grieved the loss.

Initially, there was a degree of paralysis. Over the following days, Xey discovered that they could increasingly use the surviving neural pathways directly. First came movement. Then speech. Then deliberate coordination.

At first, control required concentration. Then something changed. The surviving neural pathways adapted. Movements that had initially required deliberate effort became reflexive. Motor memories embedded in Tarin's brain began responding to Xey intentions without conscious translation.

Eventually, Xey stopped thinking about controlling the body; they simply moved.

Ironically, the result was less methodical than Tarin himself had been.

Where Tarin had preferred precise and consciously executed motion, Xey learned to trust the body's existing reflexes. Their control became instinctual, spontaneous, and increasingly natural. Medically, the result was extraordinary.

Culturally, it was horrifying.

Trill symbiosis is founded upon partnership. A symbiont controlling a host body without a host mind represents precisely the sort of relationship Trill society has spent centuries insisting joining is not.

There was immediate discussion of removing Xey. The Symbiosis Commission refused. Tarin's body remained alive, and would live for many years if no one intervened.

According to established law and tradition, removing a symbiont from a living host with good prospect for continued life merely to place it into another would violate one of the fundamental principles governing symbiosis. Tarin's parents argued that Tarin no longer existed. They wanted the symbiont to receive a new host, and they wanted to bury their son.

The Commission answered that the host remained biologically alive.

For several months Xey remained under medical observation. Starfleet physicians, Trill neurologists, Vulcan specialists, and representatives of the Symbiosis Commission studied him extensively. Repeated examinations reached the same conclusion: Xey was conscious. Xey was rational. Xey possessed continuity of memory. Xey was capable of controlling the host body.

Tarin Rel was not recoverable.

Eventually the question stopped being whether Xey was viable; the question became what Xey was permitted to do with that life. Starfleet ultimately restored him to active-duty eligibility after extensive competency examinations.

Returning to Conn proved more complicated.

Xey retained Tarin's training and procedural memory, but flying had been Tarin's passion. Without Tarin, it felt different.

Xey could still pilot.

They simply no longer wanted piloting to define them.

The accident had also awakened an intense interest in the nature of consciousness, while the scientific memories of Xey previous hosts— particularly Kella's work in astrophysics — provided another path forward.

Xey returned to training and shifted into Starfleet's science division. Previous hosts had supplied substantial scientific experience, particularly in geology, medicine, biology, and astrophysics. Supplemental Starfleet coursework converted that accumulated knowledge into current professional qualifications.

Xey increasingly gravitated toward exotic particle physics, especially phenomena encountered in deep space that did not fit neatly within established theoretical models.

In 2391, Xey received orders to the USS Fenrir.

They arrived under one name.

Not Tarin Rel. Not Tarin Xey.

Simply:

Xey.

=======

Xey has experienced six host lives.

The first five hosts were female.

Leris Xey — First Host

A planetary geologist and hydrologist.

Leris participated in extensive surveys of Trill's subterranean waterways and spent much of her professional life studying the relationship between geological activity and underground ecosystems. SThey was patient, methodical, and deeply interested in the natural world. Much of Xey's present scientific curiosity began with her.

Sella Xey — Second Host

An educator and amateur musician. Sella taught adolescents for most of her life and possessed considerably more patience with people than Leris. She gave Xey a lasting appreciation for music, humor, and the importance of explaining complicated ideas without making people feel foolish.

Marel Xey — Third Host

A physician and biomedical researcher. Marel specialized in comparative physiology and conducted research involving symbiotic organisms. Her memories have become particularly significant since Xey's accident. There is an irony in possessing a lifetime of professional knowledge about symbiosis while existing in a condition Trill medicine insists should never occur.

Jena Xey — Fourth Host

A Federation colonial administrator and diplomatic aide. Jena spent decades mediating disputes between communities with incompatible cultural assumptions. She was practical, politically perceptive, and exceptionally difficult to intimidate. Xey credits her with much of their ability to withstand hostile questioning from the Symbiosis Commission.

Kella Xey — Fifth Host

An astrophysicist and observatory researcher. Kella studied unusual stellar and subspace phenomena, including high-energy particle interactions and anomalous radiation signatures. She worked periodically with Federation scientists and provided Xey with much of the scientific foundation that would later develop into an interest in exotic particle physics. She strongly considered joining Starfleet but ultimately remained a civilian. Her unfinished curiosity about deep-space exploration became one of the influences that encouraged Xey to return to Science in Starfleet service.

Tarin Xey — Sixth Joined Personality

Tarin Rel was Xey first male host. Young, ambitious, competitive, methodical, and fascinated by flight, Tarin had spent years preparing himself for possible joining. They did not consider receiving a symbiont a prize. He considered it the most significant responsibility he would ever receive. He knew They would be contributing his life to a possibly eternal tapestry of experience. A living record of history. Tarin approached physical tasks in much the same way he approached piloting. Precisely. Deliberately. Correctly.

The joining with Xey was successful. For several years Tarin Xey existed exactly as Trill symbiosis was intended to function: neither Tarin nor Xey, but a new personality containing both. Tarin's fascination with flight combined with Xey accumulated desire for exploration. The result entered Starfleet and became a Conn officer. Then Tarin Xey died.

The body survived. Xey did too.
Service Record 2382 — Joining with the Xey Symbiont

- Tarin Rel successfully completed evaluation by the Trill Symbiosis Commission.
- Joined with Xey as the symbiont's sixth host and first male host.
The resulting joined personality adopted the name Tarin Xey.

2383–2387 — Starfleet Academy, Earth

Specialization: Flight Control

Completed coursework in:

Starship operations
Navigation
Stellar cartography
Astrophysics
Sensor operations
Shuttlecraft piloting
Atmospheric flight
Emergency helm procedures
Basic xenobiology

Graduated with strong marks in flight operations and spatial navigation.


2387–2389 — USS Asteria

Position: Conn Officer

- Served aboard a Federation exploratory vessel conducting survey and contact missions.
- Qualified on multiple shuttlecraft types.
- Participated in planetary survey operations and scientific away missions.
- Received favorable evaluations for calm, precise performance during navigation emergencies.


2389 — Katra Transfer Incident

During an away mission, agreed to serve as temporary recipient for the katra of a mortally wounded Vulcan officer.

The transfer catastrophically failed.

The Vulcan katra was lost.

Tarin Rel's conscious personality was irreversibly destroyed.

Xey survived and gradually established direct control over the host body's remaining neurological structures.

Removed from active duty pending medical investigation.


2389 — Starfleet Medical / Trill Symbiosis Commission Evaluation

- Underwent prolonged neurological, psychiatric, and legal evaluation.
- Declared mentally competent.
- Determined to possess continuous identity as the Xey symbiont.
- Symbiont removal prohibited by the Trill Symbiosis Commission while the host body remains biologically viable.
- Formally abandoned the joined name Tarin Xey and adopted the single name Xey.


2390–2391 — Starfleet Science Retraining

Transferred career track from Flight Control to Science.

- Completed accelerated qualification based upon previous Academy training and scientific expertise retained from earlier hosts.
- Concentrated in exotic particle physics, xenobiology, sensor analysis, and cognitive science.
- Retained Conn and small-craft flight qualifications.


2391–Present — USS Fenrir

Position: Assistant Chief Science Officer

Current assignment.
Medical History Xey's medical condition is considered unique.

The body of Tarin Rel remains physiologically healthy.

Cardiovascular function, respiratory function, digestion, endocrine activity, sensory processing, and motor control are all within normal Trill parameters.

The neurological situation is considerably more complicated.

The failed Vulcan katra transfer caused catastrophic disruption to the neural structures responsible for Tarin Rel's autonomous consciousness and integrated personality.

No meaningful independent host consciousness remains.

Large portions of the brain remain functional.

Procedural memory survives.

Motor pathways survive.

Sensory processing survives.

Autonomic function survives.

Some stored autobiographical memory remains accessible because portions of Tarin's memories had already been integrated into Xey during normal joining.

The symbiont now performs executive functions that would ordinarily emerge through cooperation between host and symbiont.

Xey therefore controls the body directly through the same neural interface that once allowed Xey and Tarin to function as a joined organism.

Initially the control required considerable conscious effort.

With time, the surviving host nervous system appears to have adapted to Xey's direct control. Motor commands are now largely instinctive, with learned reflexes and procedural memory responding naturally to Xey's intentions.

Xey does not normally experience themselves as operating a separate body, they experience themselves as moving. The process does not appear physically harmful.

It is not known whether it will remain stable throughout the natural lifespan of the host body but there is currently no evidence of progressive neurological deterioration.

Xey undergoes regular examinations by Starfleet Medical.

Medical safeguards include:

- Annual neurological imaging.
- Regular examination of the host-symbiont neural interface.
- Cognitive testing to monitor memory continuity.
- Evaluation for abnormal symbiont stress.
- Monitoring for degradation of motor pathways.
- Restrictions on unnecessary telepathic procedures.

Xey strongly prefers to avoid mind melds; this is psychological rather than physiological.

Physically, Xey remains in excellent health.

Tarin's body had been maintained in exceptional condition prior to the accident, and Xey has continued that regimen.

There are no chronic illnesses or permanent physical disabilities.

Xey is cleared for unrestricted Starfleet duty.

The Trill Symbiosis Commission maintains that Xey may not be removed from the current host while Tarin's body remains alive.

Should the body die naturally or become medically unsustainable, current Commission policy permits Xey to be transferred to another suitable host.

Whether that promise will survive the political controversy surrounding Xey remains uncertain.