Random facts, you say?

Hatsune Miku wrote:

Soul of Stray Demon wrote:Men can be allergic to their own semen.

 
Dunno if it's related but they say Andrei Chikatilo's(russian serial killer) semen type was different to his bloodtype, spit etc, hence why it took them so long to track him down, it was thought to be impossible at the time. If you can have different types of bodily fluid why not be allergic to one.