Let's take a look at how male climax works:
First, semen collects in the ejaculatory ducts during sexual stimulation.
Male orgasm happens at the peak of sexual pleasure, when the various muscle groups contract simultaneously.
Rhythmic contractions of the pubococcygeus muscle (pc muscle) occur along with contractions of the anal sphincter, rectum and perineum, and the ejaculatory ducts and muscles around the penis.
The contracting muscles are the key to delivering the load of semen.
The first few contractions are intense and close together, occurring at about 0.8-second intervals.
As orgasm continues, the contractions diminish in intensity and duration and occur at less frequent intervals.
The Sky is the Limit.