Hachiman Hikigaya, a student in Soubu High School, is a cynical loner due to his traumatic past experiences in his social life. This eventually led to him developing a set of "dead fish eyes" and a twisted personality similar to that of a petty criminal. Believing that the concept of youth is a lie made up by youngsters who face their failures in denial, he turns in an essay that criticizes this exact mentality of youths. Irritated by the submission, his homeroom teacher, Shizuka Hiratsuka, forces him to join the Volunteer Service Club—a club that assists students to solve their problems in life, hoping that helping other people would change his personality.

However, Yukino Yukinoshita, the most beautiful girl in school, is surprisingly the sole member of the club and a loner, albeit colder and smarter than Hikigaya. Their club soon expands when Yui Yuigahama joins them after being helped with her plight, and they begin to accept more requests.

With his status quo as a recluse, Hikigaya attempts to solve problems in his own way, but his methods may prove to be a double-edged sword.