The act of ejaculating in a woman's head of hair, causing a real mess.
Ronald gave Gretchen a sperm perm on accident. Her fault though, she should have caught it with her mouth.
by Stevie Y August 12, 2005
Its when a guy shoots a load of sperm in a girls hair, and she massages it into her scalp.
"Dude, i gave that girl the biggest sperm perm in the world last night."
by mc080290 December 15, 2006