Milk is a white, creamy substance that helps breasts develop on female mammals. Males who drink milk do not get the benefit of mammary gland enlargement, but males get something else, explained later.
The way it works is this. When a female drinks milk, the liquid travels down her esophagus and on the way to the stomach gets picked up by monotremes, which move the milk over to the tiny sacs around the nipples. If a woman is pregnant, the milk stays there until her progeny is ready to breastfeed. If a woman is not pregnant, the milk simply dries up. But either way, dry or wet, the milk makes breasts increase. Also, fatty acids in milk work well with the fatty tissues in a female’s body. Fatty acids are chemically attracted to each other, and once their atoms bond, there is no letting go. This is why women who drink milk will have larger breasts and why fat women who drink milk will have proportionally even larger breasts.
In males who drink milk, the liquid doesn’t get picked up by these little monotremes, because males don’t have those. The milk has nowhere to go but down. When food isn’t being digested, or stolen by monotremes, gravity is very much at work here. Milk doesn’t get digested in the usual way because it comes from cows and cows have too many stomachs, unlike humans who have just one stomach.
The milk passes through the stomach, liver, pancreas, duodenum, various intestines and colons, the cecum, and finally, enters the penis. The penis can only hold so much milk because it normally doesn’t have much storage since sperm is also fighting for space as it spills over from the male’s testicles. The milk literally has nowhere else to go and is “stuck” until it can be released, along with sperm and seminal plasmas.
This is why men have to ejaculate so often, to get the milk out. For males who don’t drink much milk, this phenomenon still occurs because they are most likely eating cheese, ice cream, and banana smoothies.