Being a virgin or having had sex has nothing to do with enjoying your guy going down on you and doing oral on your a LOT. I'm still a virgin and my boyfriend goes down on me all the time and it feel great plus he makes me come every time. The first time it felt kinda different but I still had an orgasm, and by the third time I was enjoying it immensely so my boyfriend started going down on me and eating me out regularly from then on. So don't worry about anything or that it'll feel weird to her or whatever or her having to get used to it. If you want it and your girlfriend wants it by all means duhh get started so that she can start enjoying having the fun without having sex and losing her virginity. I've heard and read that cumming this way for a girl is far better than by any other means including having sex.