Since Sayuri divorced her husband 15 years ago, she raised Tatsuya on her own. Since she is from a motherless family, she worked hard not to make Tatsuya feel sorry for her, took care of Tatsuya until he graduated from college, and decided on her career after graduation. Tatsuya worked hard to repay his mother's debt. Every day he goes to work on the first train and comes home on the last train, so he can hardly take a day off. And then one day, Tatsuya finally broke. Sayuri invited Tatsuya to a hot spring to cure him.
