Oujisama to Haiiro no Hibi

Atsuko, 17, lives in hardship, raised by an alcoholic father in a poor household. Her life shifts when she meets Itaru, a rich corporate heir who bears an exact resemblance to her. After Itaru vanishes, Atsuko is asked to impersonate him. She steps into his life of luxury, navigating unfamiliar surroundings and experiences. As she takes on his role, she faces the challenges and consequences of living a life that is not her own.