Other variations of this would be snowman, in which you place your fists ontop and bottom of the other persons fists, snail, in which you slide your hand onder theres with two fingers up, and turkey, where, during a high five, you but your thumb out and slam your fist into their palm so that it resembles a turkey.
To add to the affect, apologize, then go in for a hug.
When they go in for the hug also, pull back and make the jellyfish motions with your arms while saying, "JELLYFISH!"
Known to be annoying as hell.
Most jellyfish have tentacles and a basic nervous system, though they lack more complicated organs, and they are allegedly composed of about 95% water. They usually catch their prey by brushing potential victims with their poison-spouting, long tentacles, which can be anywhere from inches to several feet long.
Slang: various sex acts.
Man 1: "Did you hear what Drew & Kelly did last night?"
Man 2: "Nahh what"
Man 1: "Kelly jellyfished him again"
Man 2: "Damn eighth graders don't know how to give a proper handjob"