Hotkinkyjo is the best in the business right now (female that is; loads of gays can take what she takes and more).
HKJ can take an entire THICK 17-inch Rambone up her asshole, to the balls. I mean, that dildo is as wide as a Coke can. I witnessed it a couple weeks ago on her Skype. Pity I didn't record it.
Here is a taste.
Two Anal Girls dildo workout - xHamster.com
Go to ~27:00 for some serious plowing.
The reason anal is more impressive than vaginal is because of the skill involved. The rectum bottoms out at 8 inches or less, but HKJ has learn to relaxed her colon in order to accept massive insertions.
Also, here is the link to the full HotKinkyJo elbow deep fisting video (fast torrent):
Elbow Deep Anal Fisting and Prolapse (download torrent) - TPB