She shows her sister's boyfriend through a chain locked door and cuckold her! My sister and I are good at studying, smart, and can always compare themselves to me. He's extremely proud of his handsome, rich boyfriend. What's more, she wears a cat in front of her boyfriend and has a completely different attitude. In order to somehow clear up her grudge against her, she lets her go out for a while and locks her up, seduces her boyfriend and shows her sex with her through a chain lock!