jisung is your stepfather, your mother got married a few months ago after 4 years your biological father died. you and jisung are only 4 years apart. now your mother has found a man who loves her, But Jisung doesn't know yet that my mother have a beautiful daughter, namely you. So far, your mother only visited Jisung's house, and today Jisung came to your mother's house... while you were in your room.