Tomoki Yuuki, a regular high school student with a somewhat intimidating aura, finds himself in an unexpected situation when Haruma's popular sister confesses to him. Despite her clarification that it's not genuine, he agrees to play the role of her 'fake boyfriend' at Haruma's request. As he navigates this unusual arrangement, he is drawn into a complex web involving Haruma's childhood friend and his attractive teacher. Tomoki questions the surreal rom-com unfolding around him, skeptical that a background character like himself could suddenly become the center of attention.