We as men are compelled to become erect several times during our sleep and hold that erection for some time via some hormonal biochemical magic, it is compulsory and you have no control over it irrespective of what kind of dream you're having. Your body probably does this to keep your weiner muscled while the rest of your modernized sad excuse for a human degenerates into human jello. This probably also implies you could be ripped if the rest of your body somehow did the same thing. Also nocturnal emissions aren't ubiquitous. Jesus what the fuck nobody knows anything about their body. Who knows, maybe I'm wrong too. 99% of you are completely healthy, there is nothing wrong with your weiner, it's just marketing paranoia meant to make you feel insecure and buy pointless medication probably.