I have and it was not for me. I was dating a guy who was big into anal play and sex. I have long since loved anal sex. He loved all things anal and I enjoyed when he fingered my asshole as well as loved it when he licked my asshole. However, and this may be selfish, when he asked me to return the favor I was not so much into it.
This is where my wife is at with this. I introduced licking her ass into our sex life. And she loved it right away. But she won’t return it. Which I’m good with. But she feels I don’t do it often enough. Hopefully her next lover will have a joy in doing it to her!