Tatsuya's wife was pregnant and had gone back to her parents' place, so he was enjoying his long-awaited solo living. However, after a week of living alone, he started feeling lonely and missed having someone around... when his sister-in-law Tsubasa came over to help with the chores. Tatsuya gladly welcomed the unexpected visitor. But Tsubasa's true intention was to satisfy her own desires with Tatsuya while his wife was away. Unaware of this scheme, Tatsuya was leisurely soaking in the bath... when Tsubasa entered...
