Hiromi Takabe, a student at Siren Academy, is thrust into a cycle of supernatural vengeance following her sexual assault by classmates. Seeking retribution, she summons a demon, binding its power to systematically target her abusers. The entity colludes with her to trap the perpetrators in a cellar, where a carnivorous plant organism consumes their bodily fluids to fuel its grotesque growth.

Her retaliation inadvertently triggers the plant’s spread, as its parasitic influence extends beyond initial victims. A dormant seed from the organism later surfaces, seized by another individual, enabling further corruption of unsuspecting hosts. Hiromi’s trajectory—from victim to orchestrator of violence—exposes intertwined systems of exploitation, as her personal vendetta amplifies supernatural chaos and institutional decay.

Her alliance with the plant entity and manipulation of others reflect escalating power struggles, framing her story within the series’ horror lens. The consequences of her actions underscore cyclical violence, where vengeance blurs morality and perpetuates destruction through supernatural and human collusion.