My homeroom teacher, Sakuramiya-sensei, had a situation that required her to get married before she turned 30. However, even though she is about to turn 30, she does not have a boyfriend, let alone a fiancé. At this rate, she would be forced into an arranged marriage, and she will have to marry someone she does not like. As a desperate measure, Sakuramiya-sensei decides to introduce me, Minato Segawa, to her parents as her boyfriend. I have about 10 months until I turn 18, the age when I can get married. During that time, I will help her to look for a possible fiancé candidate. However, when I met with Sensei’s mother as a pretend Fiancé she ended up liking me… and things started to get worse and worse.