Why can't girls wanna do that stuff?! Most girls are just shy but I bet a lot of them think about it! How long have you been together for? If you've been with her for a while its not weird at all. Let her do it! You guys will have a good old time LOL
Don't listen to those guys, she is probably desparate. Say no!
Sounds like you've got a good relationship going there. If she's willing to make suggestions to you about her fantasies then there's a good chance things will remain lively between you two for quite a while. Who knows, maybe she'd be open to other "weird" ideas that you have fantasies about...
My girlfriend has done that before. Do it! It's kinky but fun.