"I'll wash your back." "Oh, sister-in-law?" Her large breasts, with their distinctive large areolas, stick to Takuya's back. His lower body immediately reacts to the soft touch. (How did this happen...?) It all started with his sister-in-law Ayaka's sudden arrival. It's already been a week since his wife became pregnant and returned to her parents' house. While Takuya is enjoying living alone for the first time in a long time, he is beginning to feel lonely. That's when Ayaka comes to help him with the housework... (Could this really be his sister-in-law's real purpose?) By the time he realizes this, he has nowhere to run...