Des:Noboru went to a local preparatory school and continued to live in a dormitory. Three years have passed, and the graduation ceremony has finally arrived. On the way home, immersed in memories, her mother-in-law, Maki, who came to the graduation ceremony as a surprise, appeared from behind with a smile on her face. She enjoys celebrating alone with her stepmother, who she secretly admires, but... Maki drinks too much and he sends her to a hotel. Noboru maintains his rationality so as not to harbor any evil feelings toward his defenseless girlfriend. However, Maki gently wraps around his body and takes him one step at a time on the stairs to adulthood...