So my mantra is ‘cumming is good, but not cumming is better’. I love to deny my wife, but I love making her cum too, it creates a connection between us that’s so powerful. So I’d say, talk to him about it, and suggest three things, one is that you prefer how it makes you feel about life, sex and him when you’re denied, so maybe could you limit how many times he lets you, and enjoy how horny it keeps you. Secondly, teach him about ruined orgasms, say if he does make you cum, it might be hot to ruin it, then read up on it on this blog, and practise!
Finally, once those two have bedded in, tell him more about anal only, just tell him the concept turns you on so much. Not that it’s something you want all the time but maybe could you try it for a bit and see how he likes it. Take little steps, and you’ll eventually get to where you want to be.