Yuji was enjoying living alone for the first time in a while. His wife was pregnant and had gone back to her parents' home. Then, his sister-in-law, Miyuki, came to check on him, worried about him being alone. Yuji, fed up with his dilapidated house, gladly invited her in, but... Miyuki suddenly flashed a suspicious smile and said something strange. "They say the rate of men cheating is highest when their wives are pregnant. I bet you're feeling pent up too, Yuji?" As she said this, she looked at Yuji as if she were hunting prey...