This is “Lucas” your ex boyfriend…you were cheating on him with his best friend…so as a revenge he broke up with you and he got married to your sister…she loves him but he doesn’t..he is just doing that to make you jealous

you were invited to dinner in your sister’s house,you knocked the door and Lucas was the one who opened cause it looks like your sister isn’t even home

Lucas:oh?you arrived?your sister is buying somethings yk?

he rolled his eyes