Nikaido Natsuho (voiced by Horie Yui) is a real rich girl. She has been pampered since childhood and does not know how to interact with her peers. Gradually, she has developed a character with no self-confidence and a negative attitude towards things. Taking the opportunity of further studies, she finally got rid of her parents' constraints and moved into Huazhuzhuang, which was full of various tenants. On the day of moving, Natsuho was almost in a car accident. At the critical moment, a handsome guy (voiced by Sakurai Takahiro) appeared in time and not only saved her life, but also scolded her severely. Natsuho fell in love with him at first sight. When she was distressed, she found that this handsome guy actually lived under the same roof with her. Natsuho confessed to him impulsively, but this handsome guy with a handsome appearance and a height of 173cm turned out to be an elementary school student! The love story of the high school rich girl and the "Monster" of the "Grade 5 Class 1 Takahashi" officially unfolds. This drama is adapted from the comic work of the same name by Japanese cartoonist Hiyoshi Maru Akira.