Rena Ryūgū, originally named Reina, emerges as a pivotal figure shaped by trauma and duality. After her family’s move to Ibaraki unravels due to her mother’s affair and their subsequent divorce, she discards the “i” in her name—symbolically rejecting the “icky” taint of her past. This fracture fuels a psychological descent: violent outbursts against classmates, self-harm driven by hallucinations of maggots beneath her skin, and a desperate belief that the deity Oyashiro-sama demands her return to Hinamizawa for salvation. In Hinamizawa, Rena crafts a bubbly “Cute Mode” persona, fixating on collecting “kyute” objects and people through her “Omochikaeri” ritual. Beneath this facade lies a razor-sharp observer who detects lies through unflinching eye contact, erupting into violence when confronted with deception or doubts about Oyashiro-sama. Her loyalty to her father propels her to murder scam artists Rina Mamiya and Teppei Hōjō, followed by a school hostage crisis triggered by Hinamizawa Syndrome—a delusional condition amplifying inherited trauma and stress. Interpersonal dynamics reveal contradictions: playful rivalry and latent romance with Keiichi Maebara, clashes with Mion Sonozaki over authority, and a protective yet manipulative relationship with younger club members Rika and Satoko, whom she adorns in humiliating outfits. Though prone to brutality, moments of clarity surface, such as Keiichi diffusing her hostage rampage, exposing flickers of remorse. Post-crisis narratives depict her attending university and later mothering Kihiro in spin-offs. Visually, her short orange hair, sailor uniform, yellow scarf, and bloodied cap juxtapose innocence with menace. Shifting eye expressions—luminous to hollow—mirror her psychological fractures, cementing her as an icon of unstable duality. Her legacy solidifies the “yandere” archetype, blending charm with threat. Signature scenes like the “Uso da!” confrontation pivot narratives from mundane to horrific, encapsulating her role in probing themes of mental collapse, trust, and survival through actions both tender and monstrous.