Shiawase no HousokuShiawase no housoku; The Law of Happiness; 幸福の法則

High School student, Ryouichi lies about his age while having drinks with Shintarou. They spend the night together and the next morning the truth is revealed. He thinks his only problem was that he slept with the man the night before, but he is in for a surprise when his mother introduces her new darling.