FORTITUDE HALL — CLASSIFIED FILE
Asset Code: FH-17 - Unit IX Entity: FH-17 - "Rinu" Host Vessel: Unit IX - "Aether" Clearance Level: Fortitude Hall Staff Only Distribution: Headmasters, Supervisors, Senior Hero Operatives, Containment Specialists
fc: Nijirō Murakami
I. EXECUTIVE SUMMARY
Rinu is an ancient inugami-class spirit bound within the engineered body of Aether. He operates as a controlled asset for Fortitude Hall and is classified as a high-risk, high-value combat entity. Rinu’s motivations are destructive, malicious, and rooted in centuries of resentment. His goals frequently conflict with Aether’s, who serves as his unwilling host and moral anchor.
Although hostile by nature, Rinu’s abilities make him uniquely suited for missions involving high-level demonic threats, spiritual abominations, and entities beyond conventional hero capability. Fortitude Hall permits limited field deployment only when monitored by senior handlers.
II. BACKGROUND
A. Ancient Origins and Creation
tw: depiction/mentions of animal cruelty/animal death in this section
Rinu was created through a forbidden inugami ritual practiced by a shadowy Edo-period clan skilled in political coercion, spirit work, and assassination. Once a loyal dog, he was subjected to ritual starvation, burial, emotional isolation, and betrayal. When his life ended, the clan beheaded him and bound his spirit with final whispered commands. He awakened as an inugami twisted by pain, loyalty, and malice.
Over generations, he served as the clan’s guardian and weapon. Rinu hunted demons, criminals, and political opponents alike. The family relied on him heavily and fed him guilt, fear, and offerings. Although he acted as protector, centuries of violence reshaped his nature. Loyalty softened into resentment. Duty warped into enjoyment of the hunt.
B. The Family’s Fall
While Rinu was away on a task, the clan was ambushed and wiped out. The last heir attempted an emergency binding ritual to pull Rinu back. Lacking experience and trembling with fear, the heir failed. Rinu materialized but met a flawed anchor and immediately tore the heir apart.
With his family gone, Rinu became a free spirit. Anchorless, he began possessing individuals who could temporarily withstand him. The hosts degraded rapidly, torn apart spiritually or physically. Rinu drifted across decades and eventually centuries, always feeding, always moving.
C. Wandering Centuries
During his time unbound, Rinu’s memories became fragmented. He remembered violence vividly but lost track of entire decades. He stalked war zones, haunted temples, lived in criminal districts, and slipped into forests like a wandering curse.
Over time he developed habits independent of any master. He stalked evildoers, not out of justice but out of twisted fun. He fed on guilt, fear, and the lingering despair of the wicked. Sometimes he possessed humans; other times he lived as a stray dog to conserve energy.
His identity became something feral, predatory, cunning, and deeply lonely beneath the hunger.
D. Capture and Extraction
Eventually, Rinu was captured by an occult research team studying spirit biofusion. Recognizing his age and density, they extracted him from his stray dog form through a harsh metaphysical siphoning process. For the first time in centuries, Rinu existed without a body. They trapped him in reinforced spiritual tanks, studied him, and prepared a vessel that might contain him permanently.
This period was agonizing. Rinu felt everything. His essence was stretched, restrained, and pulled apart. His hatred unbridled. He planned revenge in cold silence.
E. The Aether Vessel and His Awakening
Aether was grown, not born. He was designed intentionally as a living container able to withstand Rinu’s corrosive presence. His creation process involved:
Bioengineered tissues resistant to spiritual decay
Reinforced energy channels along bones and nerves
A synthetic soul-fragment lattice meant to absorb spiritual shock
A dormant consciousness that would activate only after infusion
Aether’s body was functional long before his mind awakened. Researchers monitored his vitals, adjusted his form, and prepared him for the forced merging with Rinu. They believed Aether would remain a hollow vessel.
They were wrong.
When Rinu was poured into Aether, the vessel sparked with awareness. The pain of merging ignited sensory pathways, and Aether’s consciousness bloomed at the exact moment Rinu entered him. Aether’s first sensations were:
Rinu’s ancient hatred
Blinding physical agony
The pressure of being drowned from the inside
A voice snarling inside his skull
Aether could not feel pain normally, but in that awakening moment he felt fear so intense it defined his identity.
Rinu felt everything physically — every nerve, every muscle, every drop of blood. Aether felt everything emotionally — terror, confusion, guilt, and the overwhelming weight of Rinu’s presence.
The two became one being divided across sensation: Rinu, the body. Aether, the heart.
F. The Laboratory Massacre
Rinu regained enough control quickly and manipulated Aether’s still-forming mind. He whispered instructions, twisted instincts, and ultimately convinced Aether that escape was necessary. Once Aether’s body responded to him, Rinu used the vessel to tear apart the facility.
The destruction was brutal and total. Rinu enjoyed every moment. Aether was horrified but powerless.
After the massacre, Aether gained full consciousness and panicked. He refused to leave the ruins. He believed stepping outside would let Rinu slaughter more.
G. Discovery by Fortitude Hall
A Fortitude scouting team found Aether hiding in the wreckage. Despite the danger, the leadership realized:
Aether was a new being, innocent and unstable
Rinu was eternal and too powerful to eliminate
Their fusion created a unique asset
Fortitude took them in. Aether was enrolled for stabilization and training. Rinu was contained through discipline, ritual, supervision, and the bond with his vessel.
Their fate became intertwined with Fortitude Hall — not out of trust, but necessity.
III. BEHAVIORAL ASSESSMENT
Rinu
Predatory, cunning, prideful, destructive. He seeks freedom, bloodshed, and entertainment through chaos. He cooperates only to access “worthy prey.”
Aether
Gentle, anxious, empathetic. He refuses to harm others unless absolutely required. His primary fear is losing control to Rinu.
Shared Dynamics
They fight constantly for dominance. Rinu feels the physical damage; Aether does not. Aether feels emotional and mental distress; Rinu does not. They are two halves of one existence, dependent on the other for survival.
IV. ABILITIES OVERVIEW
1. Manifestation and Growth
Rinu can expand into a massive spectral-canine form when fed on food and guilt. At full strength, he reaches the size of two semi-trucks stacked on top of each other. His body in this state is semi-physical, semi-spiritual, and visibly unstable. Manifestations include flowing shadow, vapor-like corruption, and acid-laced saliva.
2. Acid Blood Curse
Their shared blood becomes corrosive when exposed to air. Inside the body it is stable, but once it touches oxygen it transforms into destructive acid capable of burning through stone, metal, and flesh including their own body. Rinu feels every drop lost as searing pain. Aether does not.
Large-scale blood exposure causes immediate collapse of monstrous form and drains Rinu’s spiritual integrity.
3. Predatory Combat Instinct
Rinu is a natural hunter with centuries of experience stalking demons, spirits, and corrupted targets. He uses ambush tactics, spiritual pressure, illusionary projections, and psychological manipulation. He fights without hesitation and without restraint.
4. Guilt Detection and Consumption
Rinu can smell guilt like a scent on the air. The guiltier a person is, the more “delicious” and empowering they are to him. He can feed from a distance if the guilt is strong, or directly drain it through contact.
5. Pain Perception
Rinu feels all bodily damage as visceral physical sensation. Aether feels none of the physical pain, only the psychological terror accompanying Rinu’s reactions.
6. Aether-Rinu Split Sensory System
Rinu controls and interprets physical sensations. Aether controls emotions, morals, conscience, and human reasoning. This creates a constant feedback loop that can be hijacked by either.
7. Mental, Reflective, and Psychic Projection
Rinu can appear in mirrors, windows, water surfaces, screens, and other reflective media as a dog or in a human form. He can also project into unguarded minds, causing hallucinations, whispers, or presence. Psychics can feel him distinctly separate from Aether.
8. Immortality
He cannot die permanently. His essence reforms even when destroyed. He can be banished, sealed, or weakened, but never erased.
9. Enhanced Physicality
When empowered, Rinu increases Aether’s strength, speed, reflexes, and endurance vastly beyond human capability. He can tear through reinforced material, withstand spiritual shockwaves, and leap extreme distances.
V. WEAKNESSES AND LIMITATIONS
1. Blood-Air Reaction
Large-scale exposure of blood to oxygen weakens Rinu instantly. He shrinks out of monstrous form, collapses, and loses consciousness.
2. Pain Overload
Because Rinu feels all damage with supernatural intensity, overwhelming pain can destabilize him, push him into uncontrollable rage, or shock him into collapse. Aether cannot perceive this pain but will collapse due to emotional stress.
3. Not Invincible
He can be overpowered by high-ranking spirits, powerful heroes, consecrated weaponry, or entities of overwhelming force.
4. Dependency on Aether
Separation from Aether weakens Rinu rapidly. Extended distance results in near-complete inertness.
5. Starvation and Purity Weakness
Sanctified areas or people with minimal guilt diminish his strength.
6. Reflective Entrapment
Rituialized reflective surfaces can trap him temporarily.
7. Overfeeding Instability
Excess guilt or food destabilizes him, causing flickering, loss of control, or ease of sealing.
8. Sacred and Blessed Object Sensitivity
Temple bells, talismans, scripture, and sanctified grounds weaken or injure him.
9. Aether’s Mind as a Weak Point
Emotional trauma or panic in Aether destabilizes both.
10. Internal Curse Decay
The corrosive blood curse erodes both internally if feeding, rest, and containment are mismanaged.
VI. FORTITUDE HALL COUNTERMEASURES
1. Reflective Surface Wards
Traps Rinu during manifestations.
2. Stabilization Anchor in implanted Aether’s Chest
Slows down or limits Rinu’s overt control.
3. Anti-Corruption Shackles
Prevents full manifestation unless deployed, keeps Aether grounded.
4. Purified Training Chambers
Reduce Rinu’s strength without harming either party.
5. Emergency Bell Protocol
Forces Rinu to retreat inward for several minutes.
6. Senior Handler Override Technique
Authorized personnel can command Rinu directly.
7. Blood Containment Stations
Prevent uncontrolled acid spills and collapse from blood-air exposure.
8. Aether’s Mental Health Program
Therapy, grounding, and meditation strengthen Aether to stabilize Rinu.
VII. INCIDENT REPORT
Case File: FH-17-IR-219 Location: North Courtyard Training Sector Personnel Involved: Aether, Rinu, Two First-Year Hero Trainees
Incident Summary
A trainee jokingly mentioned “exorcising the mutt inside Aether.” Aether’s anxiety spiked, weakening mental control. Rinu partially seized dominance and manifested through a courtyard mirror.
Two students experienced psychic shock.
Aether collapsed emotionally. Rinu projected taunting remarks through mirrors during the aftermath.
Cause
Aether’s emotional destabilization triggered Rinu. Trainee provocation gave Rinu an opening.
Aftermath
Trainees reassigned. Mirror wards reinforced. Additional grounding training added to Aether. Rinu placed under stricter observation.
VIII. FINAL ASSESSMENT
Rinu is an extreme hazard yet a valuable asset. Aether is the only factor preventing catastrophe. Continual supervision, training, and containment are mandatory.
Threat Level: Extremely High Value Level: Strategic Recommendation: Maintain controlled deployment and constant supervision.