Rain Ryuu

Rain Ryuu, formerly Oraine Akeelise Ryuu, is a young siren who abandons an Abyssal House and makes a life on land. After rescuing Kai Tylenn from the wreck of the Intrepid, he becomes one of Kai's traveling companions, fights beside him during the Limgrell investigation, and later studies with him at Raelion Academy. (Chapters 259–353)

Biography

The Intrepid and hidden identity

Oraine enters the story in the wreckage left by the Intrepid: he kills a pirate who is about to finish Kai, pulls the unconscious boy from the sea, and brings him aboard the Melenia. Because neither Kai nor the other survivors remember seeing him on the lost ship, his presence immediately creates suspicion. He eventually admits that he used a siren charm to make the rescued passengers believe he had sailed with them, choosing a temporary deception because revealing himself as a runaway from an Abyssal House could draw his mother's agents to him and endanger everyone nearby. (Chapters 259–261)

Once confronted, Oraine reveals that he broke his mother's geas, lost his guardians during the storm, and fled a life planned centuries in advance. He does not excuse killing the pirate, but insists that enthralling a person into friendship would be irredeemable, and asks Kai and Flynn Rilei for a genuine chance. Flynn's willingness to accept him helps overcome Kai's distrust. Oraine consequently travels under the shortened name Rain, learns ordinary land customs from both boys, and recounts how his mother once used his childhood friend Peile to teach him that affection could be manufactured. That history explains why his new friendships matter and why he is determined not to reproduce his family's coercion. (Chapters 261–274)

Limgrell investigation

Rain chooses to accompany Kai and Flynn toward Limgrell rather than return to the sea he misses. During the journey, he remains with Kai inside a supernatural mist, recognizes that a large array is restricting their skills, and helps examine a Darkness-bound casket. When cloud-fairy eggs begin dying, he rejects selling or abandoning them and supports the attempt to save them. He then memorizes more than half of a collapsing runic formation before it disappears, allowing the travelers to preserve evidence that would otherwise have been lost. His formal palace education proves useful, but the episode also exposes the gap between his extensive theory and limited practical experience on land. (Chapters 275–278)

The missing-person inquiry turns into a direct struggle with the local cult. Rain tracks danger, helps move the group across Limgrell's lake, and continues fighting after he is badly wounded and captured. During the escape he uses water, ice, Gravity, Darkness, and barriers to support Kai, stores equipment and medicine in his bracelet, and trusts Kai through hazardous spatial jumps. At the lake he resumes his siren form and sings to the pursuing Aela, influencing her emotions and drawing her toward the water long enough for the group to survive. Rain cannot tell whether the charm itself or her fear that other sirens might be nearby drove her away, and he stresses that an inland lake gives him less power than the ocean. (Chapters 294–317)

Raelion and sensory mentorship

After leaving Limgrell, Rain enters the Merian Republic as Rain Ryuu and enrolls at Raelion Academy alongside Kai. An academy official recognizes that the name is probably false and that Rain is nonhuman, but his altered flesh is a real bodily transformation rather than an illusion or disguise artifact. Rain meets that scrutiny without retreating and quickly adapts to formal study, passing introductory courses and joining advanced classes. His upbringing gives him knowledge of skill paths, Green-grade evolutions, magic, runes, history, languages, and etiquette that many new students have never encountered, turning a sheltered education imposed by his family into a resource he now chooses how to use. (Chapters 318–341)

Rain also becomes Kai's practical mentor in sensory training. He explains that most people waste much of their Perception, then gives Kai exercises for separating and tracing scents rather than merely noticing stronger stimuli. At Raelion's pool, Rain combines those lessons with swimming, mnemonic practice, and Water Magic: he shapes detailed moving animals, fights with underwater projectiles that ignore drag, and lets Kai study unfamiliar techniques. The sessions improve Kai's ability to distinguish scents and enable him to learn Water Shaping. For Rain, the pool does not replace the sea, but it gives him a chosen place to practice his nature openly with a friend rather than under his mother's control. (Chapters 343–353)

Appearance and personality

Rain is introduced with pale, nearly white hair that carries a blue cast and a strikingly handsome face that repeatedly draws attention. His human guise has real legs and permits smaller alterations such as changing his eye color, which appears in several shades as he adjusts his features. In full siren form he has a shimmering tail, subtly different facial proportions, and metallic dark-gold and silver eyes. He is curious, sociable, playful, and eager to experience land food, clothing, schools, and mundane inventions, but his privileged isolation leaves him ignorant of ordinary prices and customs. Rain can be reckless and disturbingly casual about killing enemies, especially early on land, yet he is earnest about consent, loyal to his friends, willing to admit mistakes, and increasingly able to temper solitary action with trust. (Chapters 259–272, 316, 330, and 343–346)

Skills, magic, and the Guide

Siren physiology and charm

Rain can transform his entire lower body between a siren tail and human legs and make lesser changes to details such as his eyes. The change is physical rather than an illusion, but reverting to a tail requires him to be in water. His siren gifts include charms tied to the ocean: the false memories he places on the Intrepid survivors are temporary and expected to fade after weeks, and he says those gifts weaken as he moves inland. His song at Limgrell can press emotions and pull a target's attention toward water, although the scene does not establish absolute control; Rain himself is unsure why Aela ultimately flees. Sirens recover quickly from wounds, but his confidence that they do not suffer infections is presented while he is inexperienced with injuries on land rather than as a tested universal immunity. (Chapters 261–262, 272, and 315–316)

Elemental and combat magic

Water and ice are Rain's most consistently demonstrated combat tools. He casts fast cutting streams and projectiles, raises defenses, freezes water, moves a boat hundreds of meters across a lake, and uses Water Shaping for precise living-looking constructs. A separate technique lets his projectiles function underwater without ordinary drag. He also uses Gravity to lighten himself, accelerate an ally, and maneuver without a surface, while Darkness and barrier magic broaden his defense. His speed and power let him defeat marauders alone, but the victory leaves him injured and forces him to admit that unfamiliar terrain and overconfidence make solo action dangerous. Lakes provide water to work with yet remain explicitly weaker for him than the open sea. (Chapters 271–272, 294–316, and 346–347)

Education, perception, and Guide knowledge

Rain reaches the story at Yellow ★★★ in race while holding an early-Orange profession obtained after opening his Second Seal at sixteen; the profession's canonical name and skill list are not supplied. He possesses Self-Mastery and can tune many thin mana filaments at once. Years of private tutoring taught him more than a dozen forms of magic alongside runes, rituals, elixirs, languages, history, music, etiquette, and bestiology, but Rain repeatedly distinguishes that education from field experience. At Raelion he understands how skill combinations, specializations, achievements, and evolutions affect Guide paths, including the fact that Green skills often occupy more slots. His smell-tracing instruction shows a particularly refined Perception, though it teaches exercises rather than instantly granting Kai a skill. (Chapters 262, 277–278, 334–346)

Power progression

Relationships

• Kai Tylenn: Rain saves Kai from a pirate and drowning, but his implanted cover story initially makes Kai distrust him. Their relationship develops through shared danger into close friendship: Rain protects Kai in Limgrell, trusts his escape plans, becomes his roommate, and teaches him siren-informed uses of Water Magic and Perception. (Chapters 259–316 and 329–353)
• Flynn Rilei: Flynn is the first companion to argue that Rain deserves a chance after his deception. Shared stories about manipulative mothers create sympathy between them, and Flynn helps teach Rain land customs while guarding his identity. (Chapters 261–274)
• Oraine's mother: Rain's mother placed him under a geas, planned his life for centuries, and used servants and Peile to demonstrate that she could control his relationships. Breaking her geas and refusing her model of coercion are the central reasons he runs away, fears pursuit, and values freely chosen friends. (Chapters 261–264)
• Rain's sisters: His sisters give him a shell bracelet for his sixteenth birthday, each contributing a shell. The gift remains emotionally important even after he abandons his former home, showing that his rejection of his mother's control is not a rejection of every family bond. (Chapters 262–264)

Items

• Rain's Shell Bracelet: A sixteenth-birthday gift assembled from shells contributed by Rain's sisters. It is a spatial storage artifact with privacy protections, can conceal itself while Rain is unconscious, and carries his weapons, pills, money, and travel supplies. The corpus does not establish its storage capacity or all of its wards. (Chapters 262, 309, and 315)