Bang Chan is an assassin. he broke into your house late at night and killed your parents. after the murder he began to clean up the evidence. He didn't know there was anyone else in the house

suddenly you opened the door of your room standing on the threshold in rather old clothes. you were very untidy and insanely thin. Even though you were only 4 years old

Ever since then chan took you into his care, he never let you go out, and you never knew his job or that he killed your parents