The first time I dated a guy, I was 21, and it was the summer between my undergrad and grad school. He was the first guy I even kissed, and he was willing to go slow with me despite being much more experienced (he was 32). On I think our third date, we had been making out on my living room sofa for some time, and I suggested we move to the bedroom. We took off each others' shirts and pants, leaving us both in just plain white fly-front briefs. We kept making out on the bed, and after a while he slipped his hand into my underpants, and I reciprocated. After feeling each others' erect penises for a couple of minutes, he said, "I think you're ready. Stand up." So I got up and stood by the side of the bed. He said, "no, right there" and pointed to a spot a few feet away. I moved to that spot, and then he sat up in the bed and said, "now take off your underpants."
Up to that point, the only people who had seen me naked since puberty started were my pediatrician and my mom at my well child exams up to age sixteen, and then one more family doctor at seventeen. But always I had been a minor doing as I was told, letting adults see my penis, whether I liked it or not. Nobody had ever seen me naked as an adult. But he was right. I was ready. I pulled down my underpants and stepped out of them, showing him my rock hard five-and-a-half-inch erection pointing straight up toward the ceiling. He said, "you have a nice dick. Spin around for me." Then I knew why he wanted me to step away from the bed. He wanted to see me, all of me, completely naked, head-to-toe, from every angle before he let me see him naked.
He then pulled off his own underpants, and told me to sit straddling his thighs with my feet behind me. This put our penises right next to each other for easy comparison, making clear that mine was the smaller of the two. We rubbed our erect penises together while making out some more, after which we swapped places, and he told me to jerk off and cum for him. I did as I was told, ejaculating on my neck, chest and abs, and a few minutes later, he ejaculated on me as well. His penis may have been bigger, but I ejaculated more and farther. :-) Then, after a brief kiss, he said, "you smell like cum. Why don't you take a shower." As I got into the shower, he got dressed, and then once fully clothed, he continued to watch me, fully naked, finish up my shower, towel off, and get dressed myself. I think that first experience of adult nudity may have a lot to why I'm so into CMNM today.