I’ve only given so far, my ex wife a few times - didn’t tell her I was going to do it, just gradually went from eating her pussy and tongued her ass a little, she responded in a way that indicated she wanted a little more so I went all in and she really got off from that - and I loved doing it.
Have rimmed a couple guys too when licking their sack - again I don’t give them any warning, just try a little and see how they respond. It almost always gets them horned up a lot more. The one I remember more was a guy that never got any kind of head or sex from his wife, an older guy. He was pretty shy and gave some indication he wanted to experiment a bit, so I ended up rimming his ass and fingering him lightly which he definitely appreciated.
I think if you’ve never tried it, when you see how the other person responds that’s part of what might get you hooked.
Wow, amazing description, makes me want to try.