It's been three years since Yuu left home, and her long student life has come to an end in the blink of an eye, and it's finally time for her graduation ceremony. - On my way home, feeling a bit lonely without my parents, the person who came over from the other side with a smile on my face...was my mother-in-law, Yumi. - Yuu can't hide her happiness at the visit of her mother-in-law, who she secretly considers to be a woman. - Yumi, who was having too much fun celebrating their graduation just the two of them, arrives at the inn with him taking care of her. - He then receives a gift to celebrate his departure from his stepmother, who he admires, and he begins to become an adult once again.