Popcorn can be messy to eat. Often times it ends up everywhere. Crotch popcorn is popcorn that ends up on your crotch/pubic region. It's okay to eat your own crotch popcorn, but its almost always a faux pas to eat someone else's crotch popcorn...there are exceptions to this rule, however.
Faux pas:
(A guy grabs and eats some of your crotch popcorn. This will most often end up in the guy whose crotch was violated saying: "WTF man! You just touched my dick!")
Exception:
(A hot girl grabs and eats some popcorn which was on your crotch. This is totally alright.)
Having a mental database of everyone in the office's approximate package size, usually acquired through an unhealthy amount of time spent staring at passing crotches or crotches in your direct line of site
Based on Lucy's overall office crotch awareness, the new guy was going to slide into the smaller tier for sure.
Usually performed while under the influence of alcohol. While when dancing in a large group of people you stick your hand into the air with it cupped at a grabbing angle while laughing obnoxiously. You then reach down and grab the crotch of some hot unsuspecting babe. This behavior has a tendency to piss off some ladies boyfriends and to get you kicked out of clubs and bars. I speak from experience.
As Bellows drankbeer among all of the hot female dancers, he decided then and there to do the crotch dance.