Friend dating sister
You also have to realize that he’s her family, and if they have a good relationship, she will probably always be loyal to him.
Your relationship with her brother could put a strain on her relationship with you. Imagine going over to your BFF’s house to hang out with her and feeling like you have to avoid her brother?
But realize that if she hates the idea and you go for it anyway, it could end up messing up your friendship.
And please don’t hook up with him or date him behind her back.
Would you want your best friend or sister to break the news that they were pursuing a relationship?
I think it would depend on the way the friend treats women.
And forget about talking to her about your relationship.
You don’t necessarily her permission to be with him.
Lying to her in order to try to spare her feelings and make her feel less uncomfortable with things is only going to make everything worse.