I read a couple fantasy stories about men who would be punished if they ejaculated more that one spurt at orgasm. I have since talked to men about it, and most found the concept a turn on, even if not possible. I found it a huge turn on to imagine a man trying to hold back his cum at that most vulnerable moment. Only two of the men I have talked with said they could do it under intense concentration, and one guy wanted to retain most of his semen for edging. I never witnessed it myself. Don't get me wrong, I do not recommend it, and do not think it is healthy for men, just a turn on thing to talk about.