How to ask a singer to go on a date after their show?

[kat]

I have a small crush on a singer who isn't really popular/mainstream but has a pretty good following. He has a concert in my city in a few days and he's even put me on a list to get into the show for free. His drummer friended me on facebook and we talk on twitter/facebook/instagram sometimes, but he could do this to a lot of people. Anywho, the concert will be in a small location so it'll be up close and personal. How do I ask him to maybe hang out after the show and not seem like another fan girl? I've met a lot of famous singers in passing, but I'm kind of interested in getting to know him i want to ask him to go out for coffee maybe
I've worked behind stage at concerts and am pretty into the music world, but am far from a groupie. I've met many bandboys and know how they are, so i'm not talking about going backstage! I'm talking about going out for coffee or dinner and how to do it properly when we meet