Mitsu Hachinomiya, the only daughter of the notorious and influential Hachinomiya family, has spent her life surrounded by wealth and rigid expectations. Despite her family's power, she has never experienced the ordinary school life she secretly longs for. After being expelled from an elite academy for reasons tied to her family's reputation, Mitsu sees it as her chance to start over. She transfers to Ohanabatake High School, a run-down institution that her grandmother once attended, hoping to blend in and finally live a normal youth. Upon arrival, she discovers the school is a den of delinquents, filled with intimidating and unruly students. On her very first day, Mitsu is harassed by a group of thugs, but she is rescued by Sumire Kitamura, the most dangerous-looking and feared boy in the entire school. To her utter shock, Sumire immediately kneels before her and declares, "I am your maid," offering to devote his entire life to serving her with absolute loyalty. Sumire is a former delinquent who became disillusioned with the world after being told that a man could never be a maid. He takes his self-appointed role with deadly seriousness, performing every task with precision, from cooking and cleaning to acting as a personal bodyguard. His devotion is overwhelming, and he insists that Mitsu needs no one else but him. Mitsu, who initially wanted to be independent and ordinary, finds herself caught between exasperation and a growing dependence on his constant care. As the story progresses, Mitsu begins to develop romantic feelings for Sumire, but she struggles with the realization that he perceives himself only as her servant and master, never as a romantic equal. She tries to suppress her emotions and maintain her position as his owner. The narrative deepens when figures from Mitsu's past, including representatives from the Hachinomiya family, appear to drag her back to her former life of privilege and obligation. Sumire's loyalty is tested as he must protect Mitsu not only from schoolyard threats but also from the powerful family that wants to reclaim her. Through these trials, the nature of their bond is challenged, and the line between servitude and genuine affection becomes increasingly blurred, leading to a resolution where both must confront what they truly mean to each other.