When Yu was 18, she got pregnant and gave birth to Tatsuaki. The father disappeared after learning about the pregnancy. Yu pushed back against everyone's objections and gave birth to Tatsuaki alone. She desperately raised Tatsuaki by herself. Tatsuaki entered university, and child-rearing became less demanding. Because they were close in age, the two were very close. Their shopping trips and travels together looked more like friends than parent and child. One day, Tatsuaki invited Yu on a hot spring trip during his summer break…
