It's when you take roughly 100ml of mayo and a funnel, pour it in your bumhole through the funnel, and after ~10 minutes use the funnel in a reversed fashion, storing the "hot" mayo in a sock (for later use, if you plan to consume the hot mayo quick ofc, otherwise just hold it in your rectum for a much better experience).
Haha... accidently forgot to tie up my sock, and all of the delicious hot mayo spilled over me..