Kim Sejeong leads a happy normal life with her loving parents, three caring older brothers, and a loyal circle of friends. Then one day, she wakes up in someone else's body who leads a life completely opposite of hers.

Character Introduction: 

Kim Sejeong - born in a big family as an only daughter. Sejeong was showered with love especially by her brothers who spoils her. Surrounded by her rowdy brothers, she grew to be boyish, careless and bubbly. She has a big heart and always put others before herself. 

Kim Seokjin - the oldest sibling in the Kim family; he is filial and loves his little sister more than anything in the world; he is a third year in University majoring in Theatrical Arts; 

Kim Namjoon - the second oldest in the Kim family; he's quiet but is reliable; He quietly looks over his little sister; he is a second year in University studying Linguistics

Kim Taehyung - the youngest brother in the Kim family; he's playful and cheerful and likes to bicker with his younger sister; he is a third year in the same high school as Sejeong; he's overly protective of her and while he likes to tease Sejeong, he also will never let anyone bully her

Min Yoongi - the guardian angel assigned to Sejeong; He's been a guardian angel who has looked over countless humans before; he taught Jimin once at the ways of guardian angel and became friends with him; he always put Sejeong first over anyone else; 

Park Jimin - Lee Hara's guardian angel; he's still a rookie who has only looked over a handful number of humans; Because of his kind hearted nature, he often let his emotions make the decisions for him; he is tasked with Lee Hara whom he cared for so much that he is willing to sacrifice his own life to save her

Lee Hara - born in a rich family; she's sheltered and strictly raised; She's reserved, quiet and stubborn; She doesn't care what others think of her; she's often brazen and because of her own trauma, inflict pain on others; she's bullied because of this; When she finds out that she's dying from her guardian angel, she makes a request to have a chance to be happy before she dies; Through Sejeong's life, Hara finds out what real happiness is

Jeon Jungkook - Lee Hara's fiancee; born in a rich family; he grew up with Hara and only sees her as a childhood friend but their parents arranged for them to get married once he's finished with school; the successor of the company; he is brilliant, popular and is good in sports

Jung Hoseok - the Kim's family's neighbor and Sejeong's childhood friend; he's bright and optimistic, similar to Sejeong, and has a love for adventures; he goes to the same University as Namjoon

other minor characters may be announced