A young woman named Kokoro finds herself struggling after her father disappears, leaving behind unpaid debts and rent arrears. Desperate to help her sick mother, she pleads with their landlord, who uses a wheelchair due to illness. Initially, he agrees to assist her but soon begins taking advantage of his position by repeatedly engaging in sexual harassment. As time passes, his demands escalate until they reach the point where he forces her into anal sex. Despite initially resisting, Kokoro eventually succumbs to her situation and becomes his sex slave.