Back in my thinner days when I was only a B cup, my boyfriend at the time and I enjoyed tit fucking every bit as much as I do now with my current boyfriend. I don't think my size has affected it in any way other than the visual effect. Both these guys were/are breast fanatics, and their enthusiasm would flow over to me and I would get immense pleasure from it myself. Since the birth of my daughter my breasts are a lot more sensitive and now I cum from breast play, so that has changed but I don't think that is a size issue.