Living in a housing complex that has recently become the focus of nightly swarms of sinister bats, middle school student Mika Ozora finds her ordinary days unraveling into a nightmare. Strange incidents begin to multiply: infants wailing in the dead of night, mothers behaving in inexplicable ways, and neighbors vanishing without a trace. The source of the disturbance appears to be something far more ancient and predatory than a simple animal infestation. Mika’s classmate, Kuronuma Maya, is attacked by a bizarre, head‑only alien creature soon after the bats first appear. The next morning, Maya begins expelling cotton‑like spider threads from his mouth and nose, and his face twists into a terrifying vampire‑like visage as he turns on Mika. As the menace spreads through the complex, Mika must confront a reality where the boundary between human and monster dissolves, and where curses, vampirism, and alien horrors converge within the walls of her own home. The story unfolds as a tense horror thriller, following Mika and the few trustworthy residents as they try to uncover the origin of the curse and survive the escalating attacks that threaten to consume everyone in the building.