1 definition by BigCPizzle
The very foul smelling, disgusting fluid that is unfortunately a product of nonstop female masturbation, also known as "Fapping." Fap Juice is most easily detected while temporarily sharing a home with an extremely nasty woman who has a fake online boyfriend,masturbates alot and never takes a shower.
Damn, it smells straight up like FAP JUICE in your sister's room! She must have been FAPPING ALL NIGHT LONG!
by BigCPizzle March 22, 2012