Fish hook- a sexual manoevre in which one person uses a finger or a thumb to form a crudely improvised hook inside the orrifice of another, followed by exerting an outward, stretching pressure on said orrifice.

While performing intercourse "doggie-style" this maneuver involves the pitcher inserting his curled finger into the catcher's mouth and pulling back to degrade the subject or cause pain. A "double fish hook" involves the same maneuver using both fingers. A "rusty fish hook" involves fingering the ass of the catcher prior to insertion of the finger(s) into the mouth.

Putting a finger in someones mouth while trying to hurt them and then pulling as hard as you can to rip their cheek. This resembles a fish being hooked so is called the fish hook. As seen in The Gangs Of New York

using your index finger to pull down a girls shirt in order to see her boobs.

After sliding your finger into the cathedral you then curl your finger and pull back.

when you're getting head from a chick and you have a dick piercing. just before you blow you catch the piercing onto her cheek and reel 'er in and watch her squirm and squeal. that is what i call "catch of the day"

Kicking a guy in the nuts from behind and make it so your toe connects directly with the scrotum, gooch or tip of penis. Also known as a candy cane.