Asking a guy to hang out on Facebook?

[kate]

There's a younger guy (by 4 years) I met at a college party, and I randomly saw him the next day and we talked for about 10 minutes. He was really enthusiastic and really sweet (a little childish in an endearing way, but he's a football player so he's very tall and really hot and muscular).

He's a really good and SuPER humble guy and I'd like to get to know him more. I am going to send him a Facebook message (we are already friends) saying 'hey, it was really nice talking to you the other day. We should have lunch sometime! Let me know when you're free, here's my number'

Is that cool? I didn't ask his number when we talked because I thought I would be too forward.