A sexual activity in which the male (or female) inserts a gumball into their partner's asshole. Once inserted the partner with the gumball inside them will attempt to push it out and shoot it into their partners mouth at which point the partner will chew the gumball. Take caution! Every now and again "foreign matter" can be shot out from the asshole along with the gumball, it is recommended to plug your nose.
Lets go down to the store we need some gumball so we can do the Tahitian Gumball.