Lots of surprises are in store for Tennomifune Academy's Happiness Class. Not only do they have Tsubaki, a shy new classmate, but for the upcoming school culture festival, they'll be doing...improv?! Will Hibari, Hanako, and Botan (along with Hibiki and Ren) be ready to take the stage, or will their collective misfortune lead to chaos? And just why does Tsubaki's voice sound so familiar...?