Maki raised her son Kousuke single-handedly. Taking advantage of his growth, she remarries the man she is in a relationship with. Recently, for some reason, I can't help but worry about Kousuke. I couldn't help but wonder why I was starting to have bad feelings for her son. One day, she receives a letter from the hospital where Kousuke was born... It was about Kousuke not being his own son. Ever since he was young, Kousuke has secretly harbored feelings of the opposite sex towards her mother.