Lee Seunggi - Your brother who wants to become a chef . he swops identities with you 

Lee Eunhee ( You) - In order to fufil your dear oppa's dream , you decide to swop identities with him

BIG BANG

-- Gdragon aka Kwon Jiyong - A cold mysterious guy but is warm to you . Son of Mr Kwon , who owns the biggest company in korea ( Business involve Entertainment , manufacturing ,  food , etc ) . Hates it when girls go after him . Finds Eunhee cute 

---- TOP aka Choi Seunghyun - Playboy , has lots of girls fighting to date him .Open's up his troubles to you , also rich . Has a lot of girlfriends .

----- TaeYang aka Dong Youngbae - Daesung thought of this name for him as he is quite emo so he wants to cheer him up . Rich , handsome , has a personality that eveyone likes . Filial too ,

---- Daesung aka Kang Daesung - Rich , loves doreamon , cute , finds you interesting , always insulting you as you are not that tall 

---- Seungri aka Lee seunghyun - Rich , loves firlting , has a personality which girls simply cannot resist , when Daesung bullies you , he helps you .

TOGETHER , THEY FORM BIG BANG .