To fondle ones genitals, usually the testicles and scrotum, while tonguing the anus.
Lucy came over the other night, and I could not believe my luck when she got down on her knees and began to funtle me like a pro. I think she has a lot of experience from the Funtle social network. Her pussy looked like a roast beef sandwich. I think I'm gonna get myself tested now though because it burns whenever I drop a deuce.