A synonym of the word condom, which is a rubber *sock* which covers your cock while fucking. The most commonly used method on contraception after anus as it can be hidden in many places such as:
1)in pant pockets
2)in shirt pockets
3)in coat pockets
4)in wallets
5)in shoes
6)under a cap
7)between the penis and the testicles(for a male
8)between beaver-flaps(labii)
9)in a condom box
10)in your mouth
11)already on your penis.

A fucksheath can also be used in many other uses other than a contraceptive, such as:
1)a jizz-bucket
2)a baloon
3)a water baloon
4)a hat
5)a projectile
6)a term paper
Jane:"Did you bring the fucksheath?"
Joe:"Dammit!FML."

Jack:"Why are you walking funny like that, John?"
John:"I've got my fucksheath already on my cock in case shit happens."
Jack: "Don't worry. Sally wouldn't actually take a dump on your dick, man."
John:"..."
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