Pretty simple dunkshot of a amateur level. Dunker hasn't got a good flip, that's why his dunk barely graze the rim, in some cases it more looks like layup. More applyable to the beginning dunkers. Thanks.
Its when the giver cups the hands around the takers butthole and breaths hot air directly on the rim creating a sauna like experience for the takers anus.
"Dude, Stella came over later last night and gave me the hottest rimsteamer! It was like only my butthole was in a sauna!"