I really like my friends gf
What do you like about her? Can you elaborate?
She's not incredibly pretty but she's funny and sweet.
You shouldn't try and get with your friend's gf. You could hurt your friend in the process.
I've been wanting to do stuff with her for a bit now. I mean, I'm always around them.
That would be a a big no-no. If you start flirting with her you could end up losing both of them. She might not even have feelings for you and it would make things awkward.