When Hitomi was 20 years old, she got pregnant with a boy with a man who had a wife and children. She was asked by a man to let her down, but she hitomi disappeared from her man's sight and she gave birth to her Tatsuya alone. Hitomi and Tatsuya became close friends rather than parent and child. As Tatsuya becomes more and more like her father, Hitomi begins to fall in love with her. And when Tatsuya was a student, he finally crossed the line. When Tatsuya turned 20, Hitomi invited him to a hot spring trip to celebrate.
