I've been with this vocal girl a couple times now, and I can't, for the life of me, figure out if she has cum or not. So, I've just been trying to give it a good amount of time before I give in myself. If I were going off of her voice inflection I'd say she was cumming two or three times, but I can usually feel it too, and I'm not feeling a thing. Should I just ask in the middle of sex if she is good? I think that is kind of weird, but I don't want it to be just about me. Any suggestions/advice?