Mizuki Yoikawa (31), who is unable to have a boyfriend and has a series of bad luck with her company going bankrupt, returns
to her parents' home after a long absence and meets Ren Hebimori (20), a mysterious younger boy.

She comes to know his insane nature and is half-forced to become his lover.
Furthermore, the words to the next step from his mouth early, "I want to say a wedding greeting."

When she reluctantly took him to her parents' house, he met her mother and
her cousin Sho-kun, who seems to have helped her with the shopping.

He can't hide his jealousy at the presence of a man who is close to her, even though he's a relative.
And while her mother is very supportive of the marriage, her cousin calmly tells her that Hebimori is
still a student and that it's too early.

Ren-kun begins to run wild against negative opinions about their marriage. In order to avoid the worst situation, she should have just calmed him down..

This is the story of a young yandere boy who is sweet and doting and a little bit brutal and disturbing]