Receiving oral sex puts me in a very vulnerable position. And vulnerability is nice, but it can also be a bit scary. I am practically always open to receiving it, assuming there are no clearly visible dental health issues on the part of the giver, but I always start off of a little hesitant. I suppose it's safe to say that I hope for the best and kind of expect the worst lol.
Luckily, I've never experienced anything horrible like biting or pulling, but I have experienced things that I don't particularly enjoy like excess saliva or hard clitoral sucking. Generally, I'll just switch to something else if I'm not enjoying things. It's hard to "teach" someone the most pleasurable way to give me oral sex in the limited time that we'll have together. And I'd much rather we do things that I enjoy that are easier to explain like being slowly fingered or having my nipples softly sucked.
There are so many wonderful way to provide pleasure to a woman, we come equipped with all these beautiful, arousable body parts. If you want to pleasure the companion that you're with ponyman49, just ask her what she'd enjoy. She may say daty, or if she's like me, she may say that she'd love for you to get on top, slip inside of her and stroke her slightly while she rubs her clitoris.
Ultimately, it's your fantasy to fulfill. And if you desire to just dive face first into a yummy pussy, that's perfectly ok and completely understandable. But don't do it under the guise of wanting to provide pleasure to her, if your goal is really just to enjoy the experience for yourself.