Nothing.
Some men enjoy consuming their own semen for sexual excitement or even just for the taste. It does not make the male a homosexual because the sperm is his own, to be a homosexual the act needs to be performed on another male.
There are actually healthy benefits to consuming semen. See the related link below for further information.
While it's strange to desire to consume one's own spermatozoa, I'll humor you. Unless you have some form of genital disease/STD, then you will simply ingest the sperm, and presumably the semen. If you are suffering from some form of genital disease/STD, then it's quite possible that consuming your own sperm will result in a spread of the infection, which would be bad. If you want to ingest your own sperm and you're clear of infections, then knock yourself out. If you are suffering from infections, I'd urge you not to eat your own sperm.
that's a major safety hazzard
Nothing happens when a man ingests his own semen.
their own sperm
No
It's perfectly normal and safe to eat it, but if it's not your own, you can get an STD
There is nothing that will happen if your own sperm comes in contact with a cut on your body.
their own sperm
It is digested in the stomach. It does not contain anything harmful, if the person who it came from is disease free.
Giant squid eat there own kind (giant squid!)
it will get stuck in your small intestine.
yes, nothing happens if you do
you get hair balls in your body
Sperm Whales just swallow these things. They usually own sharks but sometimes sharks own them. Squids have been known to be carnivores and eat these too.