Sayuri divorced her husband 15 years ago and raised Tatsuya single-handedly. To prevent Tatsuya from feeling sorry for being in a single-parent household, she worked tirelessly, taking care of him until he graduated from university and decided on his future path. Tatsuya worked hard to repay his mother's kindness. He commuted to work on the first train and returned home on the last train every day, barely taking any days off. Then one day, Tatsuya finally broke down. Sayuri invited him to a hot spring to recuperate.
