After accidentally entering a novel and binding herself to a romance system, the heroine receives a mission: she must win over the novel's top male lead to return home. She gives it her all to raise his affection level, going to great lengths to get close to her target. But halfway through the mission, she is shocked to discover that the system made an identification error. The man she has been desperately pursuing is not the original male lead at all, but merely an insignificant side character. Originally aloof and taciturn, this side character gradually develops genuine feelings for her as they spend their days together. Thus begins a hilarious and sweet romance sparked by a system blunder. What started as misplaced affection ultimately turns into true love, with both hearts choosing each other.