i've download it and watched the movie
no offense but maybe u're eyes mistaken or u have a bad quality monitor/media player.
it's not entirely cum,the 1st one and 2nd time it's a cum arround 3rd times it's a PISS:exhausted:
it's not impossible!!
my theory is the guy have ejaculated 1st, then a couple of hours he's doing it again by getting a handjob in this movie(u can see his dick is not hard enough in the couples of minutes) which is possible to produce sperm but at a very little quantity,then when the sperm comes dry he's forcing his dick to cum again which result the piss come over.
CMIIW