Tsumugi’s mom marries to a guy Named Ryo Hirano. Because of her mom previous unsuccessful marriage, she grown into a cheeky tsundere girl who lacks of manner and has no respect towards men. Tsumugi and Ryo always argue each other for every single day. Ryo who can’t stands with Tsumugi’s behavior, laids a trap for her. Tsumugi finds Ryo’s phone lying on the table and saw an unopened message on his phone. When she opens the message box, she gets surprised that her bestfriend sent a sexy photo to him. Tsumugi confronts her step dad to ask the meaning of that message. Didn’t realises that she was being trapped, she gets striked back and punished by Ryo. A punishment that would make her become a more respectful woman.