Everything posted on the Internet isn't necessarily real or what it might seem. In this particular case, what you don't see is what he did to get to the point of ejaculation. The clip starts just a moment before ejaculation begins. What happened before was edited out.
While the male body responds to sexual thoughts with erections, it isn't able to progress beyond that point without physical stimulation (touch) of particular areas. It is during physical stimulation that semen moves into the ejaculatory duct and is prepared for ejaculation. Then, as the man nears peak sexual excitement, the body reaches a point of no return -- an ejaculation will occur and nothing will stop it. That is why he was able to film the ejaculation without his hands near his genitals.
It isn't possible to just being standing there and have an ejaculation. It is possible to have a bit of fluid drip from your penis while having an erection. That clear fluid, called pre-cum in slang, comes from the Cowpar's glands and flushes out the urethra prior to ejaculation. But an ejaculation requires additional physical touch to trigger.
In regards to his pubic hairs, it appears that he is partly shaving his hairs -- something I would not recommend.

