I thought it might not be real because of the way he hides the base, but at the end he loses the pants.
It could be real, I'm sure they're out there. He wouldn't go unconscious: the blood isn't leaving his body or leaving the circulatory system, it's just being slowed at the exit. People give a pint of blood all the time: and that leaves the body. Also his flaccid is part of his body and I'm sure he'd be quite the show-er.