A high school girl, Mikoto Ochiai with excellent grades but a pessimistic attitude, is about to commit suicide by jumping off the roof of her school because of heartbreak, when her physics teacher, Jin Haiba stops her.
Haiba, who came to the rooftop to smoke cigarettes in the middle of his class, making the students have self-study class, is looked down on by his students and nicknamed “Haijin”(cripple). Mikoto, who was about to commit suicide, also feels sorry for him. “Love me before you die,” says Haijin to Mikoto. Is it only to stop her from committing suicide or a sincere confession? Unable to judge from Haiba's demeanor, Mikoto, who decided not to commit suicide, is somewhat attracted to Haiba, even though she despises him for other reasons.
Haijin then starts talking to Mikoto more and visits her home every chance he gets. And then the arrival of the handsome and highly competitive, freshman idol Takamine stirs up their romance.
“I'm the only one who can follow you around, JK.”