In this charming romantic comedy, a shocking case of mistaken identity at birth sets off a whirlwind of chaos for two teenagers. Nagi Umino, a diligent and serious honor student, discovers he was switched at birth with the boisterous and carefree Erika Amano. To correct the error, their parents propose they get engaged and live together as a couple. Nagi, who has a secret crush on his classmate Hiro Segawa, is initially resistant, while Erika, a spoiled rich girl who has run away from her family, sees the arrangement as a convenient escape. As they navigate the awkwardness of their new forced cohabitation, their personalities clash and spark. The series blends slapstick humor with heartfelt moments of young love and self-discovery, exploring themes of family, identity, and the unpredictable nature of fate. With a lively ensemble cast including Kaito Ishikawa as Nagi and Akari Kito as Erika, the show delivers a delightful and often hilarious look at the tangled web of relationships that forms when two strangers are thrown together by circumstance.