I like my sisters good friend...what to do?

[Steve]

My sister has been friends with this girl for maybe two or three years, they are not "best" friends but definitely top 3...i recently started talking to this girl more and more and eventually we starting hanging out...behind my sisters back but always with other people around...more recently we decided to hang out just the two of us and shortly after we were laying in a field holding hands looking at the sky...she seemed like she wanted me to go to the next level...but every time i couldn't help but realize how upset my sister would be if she ever found out...so thats as far as things went for the night...she has a twitter and i don't (not to sound like a total creeper) but i wanted to see if she was saying anything about that night and she said things like "last night>>>" and things along those lines...now i have spoken to my sister in the past about "what if i hung out with your friends without you..would you care?" and the response was veerrrryy negative...so i feel like if i were to try and explain it would go downhill....but i do want to take things to the next level with this girl and ask her out....not sure what to do....if i tell my sister i feel like she will try to tear it apart but if i dont i feel like i will be trying to live a huge lie...please help...

[Manny]

HIT THAT SHIT

[D K]

You have to tell her. And let her know you have real feeling for this girl and you have to see where they go. Although it is your sisters friend, she doesn't own her. If you like the girl and she likes you, you don't need permission. But you can't hide it.