Ass (butt) in the air, posed, waiting for sex. Sexual position.

A greeting found in some parts of the mid-west United States where in partners stand very close and proceed to press their pelvises together whilst knocking on the butt cheeks of their brethren with their fists. Quasi-sexual. Usually reserved for close, or odd persons. Alien in human nature, not in a cosmos way.

An alliance of or with reptilians, in the extra terrestrial context.