When after fingering another's butt you have a particular stench on your fingers. Similar to what happens with fingering a vagina.
Damn those butthole fingers smell like shit!
by ZiggyZ21 November 20, 2016
Stemmed from an inside joke about Pizza Tower, "Mach Finger Butthole" Is a nonsense term referring to a rambunctiously high speed.
by ZynexGD December 11, 2024