Yonhyakunijuu Renpai Girl

A boy named Haru Tsuwabuki attends St. Cinderella Academy, a school predominantly for beautiful girls. To survive, he must confess his feelings to one of 420 girls, or face severe consequences. Initially mocked as a "parasitic biting insect," Haru struggles at the academy. He meets Miyako Dokuutsugi, a girl known for her bad luck. Their encounter marks a further decline in Haru's already difficult situation.