JUL-213 Mother's friend.

Yu also used the long vacation from college to go back home to meet his friend Rin, who was always in love with his mother, whose heart started to stir up the night when he learned that she was staying at home and that he couldn't sleep. He can't help but be impetuous and proactive, and he's excited about their secret. She's upset about having sex with her husband because she doesn't like her husband.