Term used to describe a sexual act in which a male places his penis in between a female's large voluptuous breast (preferably oiled up) and humps them gleefully.

It is essentially a term used to describe a titty fuck, preferred by females who found the first term grotesque when asked to be a part of the activity.
I was so excited to be balling mellons with her and that rack that I accidentally ejaculated all around her neck after four humps leaving a marvelous pearl necklace.

Guy:Baby, can I um...titty fuck you.
Chick:No, just what type of woman do you think I am
Guy:Oh, my bad, I mean uh..can we get some mellon ballin going on
Chick:...Yeah sure, why not.
by n0ci nasty September 5, 2009
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