Originally posted by
I would suggest not to talk to him directly. That is going to make him consicous about it. Just start touching around his asshole playfully, without penetration.
If someone was going to be playing around my bum, I'd want a heads-up.
I've heard plenty of stories of one partner touching around the anus without letting the other know, only to be greeted with a "what the fuck are you doing?!" kind of reaction that completely killed the mood.
This extends to just about any kind of play, when you think about it. For example, I wouldn't be too happy if a guy was into golden showers and just decided to go ahead and pee on me without saying anything. Communication really is the best way to go.