Karin Sakuma is a 16-year-old girl whose idealized standards for the perfect guy have left her without ever having a boyfriend. This importance on how something looks even extends to things she buys, often without practicality in mind.
One day, Karin's mom sets her up on a blind date with Takuma Morino, a guy who satisfies all of her requirements, but she later discovers that he is also overweight. Although Karin doesn't initially recognize him, she and Takuma had once played together as kids, during which time Takuma developed feelings for Karin and asked her to marry him, to which she nonchalantly agreed. Although he asks her to marry him again, she turns him down, but Karin later tells Takuma that she wants to spend more time with him to see what will come of it.