Yep, that's right.
Lesbian porn.
There is a whole group dedicated to it here on dA.
Now mind you, a lot of it is within dA's mature content policies, but there are some... Rather explicit images in there. Honestly, this group is mostly a spank bank it would seem.
Now please, do not take this the wrong way and think me homophobic. A lot of my good friends are lesbians and I have no issues with people being allowed to love whom they wish, but that does not mean I want to see them getting eaten out or their tits sucked on. Even if it was all straight I would probably still have a problem. If I want to look at porn, I'll go elsewhere. But I do not want to see it on my dA.
Artistic nudes? Sweet! 2 ladies posing together naked in a well shot and thoughtful artistic way? Sure. Fetish portraits? Not my thing, but ok. Licking pussy and fingering each other? No thank you.