A sexual act where one partner is crouched down moving side to side, scuttling like a crab. The other partner, a dude, is about to bust a nut in his partner's face when he feel an explosive bout of diarrhea coming on. Instead of busting his nut, he quickly does a 180 and treats the crab-walker to his hot beef stew.
This is named after the city Canton
, in Ohio like the inspiration for so many other acts involving dookie.