"Entre broma y broma la verdad se asoma" google translation: Between jokes, truth looms.
A saying in Spanish. By the story seems this man had a hard time being frank when it comes to sex. Sometimes jokes can be used to talk about an issue, while at the same time not talk about it. If he continuously jokes about other issues, take that into account and just ask directly (e.g Are you interested in losing your virginity?).
About your sexual encounter. You were jacking him off, he tried to stop you (don't know if he verbalize it, such as stop or slow down) but he communicated that he wanted to stop, you continued cause you wanted him to cum. Don't know how was the experience for him, maybe it was sour, maybe it was good.
Considering this guy is a virgin, and don't know how much weigh falls into his virginity. I think it was a good thing that you guys didn't went "all the way", and to take this time to talk about openly. Therefore having a better understanding about your desires, wants, needs and boundaries. And you can shout such lines as:
"Yeah but look at it, my butthole is so widespread, man" credits to Sphynx.