When your doing a girl doggystyle, after inserting your finger in her butt, you reach up and fish hook her. All while saying "Got one on the line!"
"Man, last weekend I caught the biggest girl in the bar with a dirty fish hook"
When you stick yer finger up a chick's poop chute, hop on her back, stick yer finger in her mouth, and give the 'ol fish hook.
Clay couldn't wait to give his wife the dirty fish hook and make her taste her own feces.
While making love doggy style, you stick 2 fingers in her asshole. Then remove the fingers and reach around to her face, in one swipe wipe her upper lip with your index finger "Dirty Sanchez". With your middle finger simultaniously hook the inside of her cheek "Fish Hook".
Did you see how pissed she was after I gave her the Dirty Fish Hook?