The act of taking a particularlysmelly shit, especially in a public restroom, leaving a stench that lasts for hours and forces others either to gag or to hold their breath until they exit the facility.
A reference to the character Reiner Braun from Attack on Titan. Reinering refers to an act in which a person gets so involved in a lie or a fake aspect of their life that they get lost up in what to believe in.
"Dude I accidentally stayed with my second family all the way until Halloween. I'm totally Reinering myself"
"Remember how Jack get pretending to be retarded? Turns out he got diagnosed with autism. Talk about Reinering yourself"
similar to moosing The man penetrates his lady friend in the 'doggy' position. At the point of climax, he puts his hands to the side of his head, palms open and pointing forwards, with the thumbs pressed just above the ears, representing antlers. Moose-esque sound effects/shaking of the head are optional but performed at Christmas time