Koichi, injured in his arm and struggling with daily life, found support from his neighbor, Tsubasa. Originally highly sexed and bold by nature, Tsubasa began to manipulate Koichi the moment she discovered his vulnerability. Through her control, Koichi's hidden masochistic side was awakened, and she enforced strict ejaculation management using a flesh-colored vibrator. Enthralled by the abnormal pleasure, Koichi found himself increasingly drawn to Tsubasa. After one week, his mind was completely dominated by her.