Anyone else's partners?

So whenever I give my boyfriend head or a handjob, he stays hard after he has cum, but he says that when he does it himself it always goes down straight afterwards. When we have sex he also stays hard and thinks that after a 5 second break he could go straight back for round 2, but we havent tried that yet. He doesn't get tired like I thought most guys did either. Does anyone else's partners have similar situations?