TBH, I don't remember if it was my first time cleaning up, and I don't think it was, as I always had a cum fetish. When I was 18, my young wife was 20. We'd been out on the lake with a older friend - maybe 23, lol. After we went to his house, we got naked, putting our clothes in the dryer. So we smoked a joint, had some music on and one thing led to another, and we enjoyed a threesome. It was very hot, and a new experience. I was a bit shy because his cock was at least a couple inches longer and fatter than mine. Watching his cock slide in my young wife was 'very' exciting, and he fucked her well. I climbed up for my fun after he had cum, and got my very first silky seconds after a larger cock. Needless to say, I didn't last but a few strokes before cumming. I remember being embarrassed by that, didn't know what to do, so figured I'd eat her to bring her to orgasm.
So, my first recollection of eating another man's cum, and a silky seconds filled pussy. I've been at it ever since!