Komachi Hirotaka has optimized his high school existence for minimal drama: get roasted by underclassmen, fail to impress the student council president, and follow his favorite idols. It works well until a new transfer student named Hanamaru Mari walks up and announces in front of everyone that she is in love with him and wants to be his girlfriend. This single confession unleashes a dormant competition that pulls in a girl who has been waiting patiently for years, a devoted junior who would do anything for him, and — uncomfortably — his own sister. Hirotaka remains largely unaware of what he has started.