The act of orally stimulating your lovers genitals from behind, resulting in either:
1.) Your partner getting rug burn between their butt cheeks from your mustache.
Or
2.) Your mustache collecting lint and other debris from the inadvertent action of stache-scrubbing their anus.
Named after 2018 Olympic Gold Medalist Matt Hamilton.
I gave him the Matt Hamilton last night. Ever since, he's been walking funny, and everywhere I go smells like butthole.