Cum. Stuff that comes out of a guys cock (no not a rooster).
"His fishpaste tasted way better because i made him eat fruit."
A bi-product of vaginal liquids stored in the vagina over time which has femented into a fishy tasting paste.
Kevin Block: "I tried to go down on my girl last night but her coochie smelled like a dead fish."
Walter: "Bro just wait until you find the fishpaste down there."