From Natalie.mu:
Mochizuki Nobara, who is often described as "serious" by those around her, is an ordinary second-year high school girl who yearns for romance but has yet to experience her first love. At the start of the new semester, the teacher asks her to help a student who has been absent from school to catch up with classes. However, that student is Setohara, an infamous boy who is the subject of many unsavory rumors around the school.