Makoto Aiba's life is defined by familial fracture and trauma. His mother’s death in his childhood left no memories, while his father’s persistent absence due to business fostered a fragmented home. Initially residing with his older sister Misaki Aiba, this stability shattered when his father remarried. The arrival of stepmother Natsuki Aiba and stepsister Yuna Aiba intensified Makoto’s stress, driving him to daily, compulsive masturbation as an outlet.

A traffic accident hospitalized Makoto, exposing him to supernatural forces. During his confinement, he encountered an old friend working as a nurse and fellow patient Hina Kasukabe. A mysterious salesman then provided a game enabling forced interactions. Trapped in his hospital room with Misaki, Natsuki, and Yuna, they were compelled to play this cursed video game adaptation of "Sexual Pursuit." The game barred escape, external aid, or cessation of play. Each turn dictated escalating sexual acts—beginning with massages or kissing and advancing to intercourse and lesbian encounters—enforced by the game’s curse.

Progressive sequences triggered intimate encounters between Makoto and his stepsister Yuna, then his stepmother Natsuki. During one interaction, Natsuki bound Makoto with rope before releasing him with a reprimand. The game persisted until all sexual objectives were fulfilled, irrevocably altering family dynamics. Hina Kasukabe overheard events from an adjacent room and briefly entered before medical staff removed her, failing to interrupt the game’s progression. The aftermath remains unrecorded.