One day, Yō Hazakura, who feels that going to school is pointless, witnesses Marin Akimi, one of the two most beautiful girls in school, lose out on her love. The look on Marin’s face as she walks away makes him pause for a moment, but then he follows her to the rooftop to talk with her. From there, Yō makes a promise to her. After this, the two started hanging out with each other. They started to be together at school. After the people around them heard the words that Marin threw at him, they misunderstood that the two are dating― And for some reason, the winning heroine of this time, Kasumi Nemoto, turns against Marin. Kasumi Nemoto― is a childhood friend of Yō.