The term used for an act of hetrosexual males replicating the intimate and affectionate nature of females (usually incited by estrogenically driven excitement and joy) with one another, including but not limited to: hugging, rear grabbing, compulsive giggling, breast fondling etc. Most oftenly used by males as a source of humor and slight means to bond. The inverse of this is boy sex to females.
TJ: Dude I haven't at the beach in so long!
Ricky: I'm so stoked! (Splashes TJ and Hawk)
Hawk: If we were girls, we'd be having sex with one another!
Ricky: ...girl sex.
(Hawk and Ricky proceed to splash each other and TJ and giggle like women)