The premise of "Usami-san to Kamei-kun" centers on the lives of two high schoolers, Usami and Kamei. Usami is described as logical and effective in her actions, whereas Kamei is carefree and comes from a prestigious family with an actor for a father. Despite Usami's impulsive tendencies, she falls for Takeshi, Kamei's childhood friend, and makes the decision to confess her feelings to him immediately. However, Kamei opposes her plan, convinced that it would only bring trouble for Takeshi.