Everyone knows whales have huge penises, they even make the sea salty with all their semen. A slippery sleeping bag is the act of climbing into a whale's penis, cause you'd totally fit.
"So I saw that Bear Grylls where he slept in a dead camel, apparently the desert is cold at night. Weird I know. So anyway, I figured it might work the same with a whale's penis, but I was all wet so I was still cold.
Still though, I'm gonna copyright it, so Bear Grylls can't talk about the Slippery Sleeping Bag without paying out.
When a male and female are getting intimate and the girl is giving the guy a hippity handjob. Then the female, without the male's knowlege, hops on top for a slippery suprise, often making a slide whistle noise.
Hey guys, that bitch just gave me a Slippery Whistle!
I was shocked when that girl gave me a Slippery Whistle in bed!
A sexual term which entails someone jacking offa man. When he cums in the hand of that person, he/she rubs it all over their fist to lubricate it, and proceeds to fist him anally.