There's a new student council president, and the Service Club's first job for their new leader is to help set up a Christmas event with another school. The problems keep piling up, but Hachiman keeps taking on task after task by himself! What's going to happen to the relationship between Hachiman, Yui, and Yukino from here?

“Let me throw your life out of alignment.” The prom goes off without a hitch, and Yukino announces the end of the Service Club’s activities. Hachiman just can’t accept it, though. Hachiman’s actions are a big surprise, but what are they...?

A sudden accident first brought together Hachiman Hikigaya, Yukino Yukinoshita, and Yui Yuigahama. Then they became the Service Club, helping others with their woes while working through their own complicated emotions. As the club now fulfills one last job—throwing the best interschool prom they can—the trio must think about how their relationship has changed and what future lies ahead for them. Their youth romantic comedy, mistakes and deviations and all, concludes here!

The fake prom scheme has run its course, so it’s time to end the charade and relax a little with a karaoke party! But as the festivities wind down, Yui has a very personal request for Hachiman...one that has him thinking seriously about her. With the real Soubu High School prom on the horizon, what better setting is there for some classic teen drama?

Haruno orders Hachiman to leak the plans. Falling right in Haruno’s trap, Yukino’s Mother goes to the school to put a stop to the prom! And as Yukino and Hachiman discuss what happened with their little “competition,” something between them begins to shift...