Yu entered a boarding school at the same time as her father remarried. His student life came to an end in a blink of an eye, and on the day of his graduation ceremony, his longing mother-in-law, Kanna, came running to him with a smile. Yu, unable to hide his joy at the visit of his beloved, celebrates with her that night. The two of them talked through the night, and their thoughts got through to each other. "A present for grown-up Yuu-kun," Kanna gently kissed. And he climbed another stairway to adulthood.