No lube for anal sex is insane. I wouldn't even consider it. Misato36 - your post rather concerns me.

Rule #1 about anal, especially for newcomers - There is absolutely no such thing as "too much lube". Get messy. Get it everywhere. But get a lot of it.

Rule #2 - Proceed slowly. He's not going to get his cock in there the first time. Or at the very least if he tries it's not going to be comfortable at all. And actually fucking your ass, it takes time to build to that. there's a reason "anal training" often starts with a very small plug, then a less small plug etc.

Rule #3 - Being relaxed is important. Tensing up causes everything back there to get tight. Often too tight. The more relaxed you are the better.

Patience is a virtue in this department from what I know.