Kaito enjoys living alone again when his wife leaves for a one-night, two-day trip. Satisfied with having the apartment to himself, his expectations are quickly shattered when his sister-in-law, Suzu, suddenly shows up. Claiming she came to help clean the messy room, her true intentions were elsewhere. Suzu's real goal was to satisfy her desire for Kaito while her sister was away. Unaware, Kaito relaxes in the bath—only for Suzu to appear before him...