Saki suffers fractures in all four limbs, requiring three months to fully recover. Tired of her monotonous hospital life, she decides to leave against medical advice and return home. Worried about her inability to do anything alone, her husband asks his college-student brother-in-law to take care of her as a summer job. With her limbs tightly immobilized in casts, Saki depends entirely on her brother-in-law for everything—going outside in a wheelchair, eating, using the toilet, bathing. In this helpless state, she can't resist anything he does, and under the guise of "caregiving," he begins to take advantage of her. Until she fully recovers, the obedient older sister-in-law becomes his personal flesh dildo.