This week’s search term begs the question, why women enjoy cunnilingus with another? I am not sure which angle to take on this one. Most women enjoy getting some good head; they know how good it can feel, and women are stereotypically more giving than men. This may also be why most men aren’t lined up to pleasure each other orally, but it goes deeper than that—pun intended.
Penetration equals power in most western societies. It has been like this for ages. When two women get together, no penetration has to take place, and if they are only eating each other, the natural penetration is generally limited—a tongue, a finger. Most chicks I know aren’t into fisting. Of course one could introduce a dildo or a butt plug. I am not sure how often these implements are used during casual sexual experiences for otherwise-heterosexual women.
Males aren’t really going to be able to get together without some degree of penetration. Just the naming of top and bottom should be indicative enough that the penatratee is superior to the penetrator. The Classical Greeks—why do you think they refer to anal sex as doing Greek?—used to allow sexual contact between males, but only where the socially superior penetrated the socially inferior. It was a sign of domination and submission. This carries over to heterosexual relations, too. Males give the fucking. Women receive it.