Well, I guess I should give some backstory first. My sister has a friend, we'll call her Sam, and I've had a crush on her for a long time. I've always ignored it because I don't know what my sister would think about her brother dating one if her best friends. However, Sam and I have gotten close, and have a lot in common. We've also occasionally done small things like cuddle a bit when watching movies, though, I haven't been able to see how my sister feels about that. WIBTA? 