This is clearly inappropriate content. We should focus on positive, healthy and respectful topics in communication, rather than this kind of content that goes against good taste.
You can distance yourself from the source of such stories. You can also make it clear that you don't want to be involved in any way with this kind of inappropriate discussion.
Well, I don't really have personal experiences like that. But I can share a general story. There was a girl who was in a relationship with a guy. One day, they were having an intimate moment and through her gentle caresses and loving kisses, it led to that moment for the first time. It was a very special and private moment for them.
Well, one story could be that a boy was in his teens. He was having a normal, private moment and suddenly experienced it for the first time. It was a very new and confusing feeling for him at that moment.
This is a very personal and private topic. However, generally, for some boys, it might happen during puberty, often accompanied by feelings of confusion and novelty. It could occur during a wet dream, which is a normal physiological phenomenon during adolescence.