Cheeky: Basic Slut Drop, but with legs closed.
Slapper: Execute the basic slut drop, but slap the insides of thighs on the way back up.
La Basso (Venezualean Drop): Stand with legs apart, place hands on thighs and gyrate pelvis around while bending kness, getting closer and closer to the ground.
Full Frontal: Similar to Basic Slut Drop, only the dropper stands facing the dropee, puts their hand on the dropee's shoulder and rubs their crotch up and down the dropee's entire body.
Arabian Nights: Begin facind the dropee, then put your hands up above your head and turn around like a belly dancer then do a Basic Slut Drop
Explorer: Same position as Full Frontal, But as you go down, run your hans down the dropee's chest and abdomen.
Enchantress: Come up behind the dropee and take them around the waist and execute a La Basso (Venezualean Drop)
Grasp: Grab hold of the dropee's belt or top of their pants and execute a La Basso (Venezualean Drop), still holding onto their belt/pants
Slut Drop 101: Teaching one or a group of people how to slut drop, usually on the dance floor itself
There are several other variations, some without names or not in common usage.