How to approach pee play with a piss virgin?

[AugustWet42 19]

Hi everyone! I'm pretty new to this group, but I've had a pee kink for a long time now. It really started with watching desperation wetting and then eventually getting into watersports and even diapers. I had two exes that knew about my kink, and both of them would pee with me and would tell me stories of girls they saw peeing to turn me on. The first one wet diapers with me in public, and we did basically everything under the sun together. Drinking each other's pee and peeing anywhere but a toilet were common rules when we were having our sex nights. I didn't know until after we broke up that she wasn't really into the diapers but did it to make me happy. She was neutral about it I suppose. My other ex that peed with me drew a hard line before that so I didn't even play diaper porn in front of her. But I drank her piss, pissed on her pussy and she'd often piss on my cock. Once she had a real life wetting accident and her panties were completely soaked.

My kink has never been an every day thing, I usually indulge a few times a month and we had vanilla sex the rest of the time..  but she knew how hot I would think it was if she made me wear them to the new year's eve party we went to that night. It was super dirty feeling her wetness on my cock all night with no one the wiser, and it was great to share that with someone who also enjoyed it again.

This brings me to my FWB. We had watched piss porn together years ago so she also knew about my kink. We stopped talking for a long time while I was with my second ex, and apparently in the meantime she has developed a full blown piss fetish! I get the dirtiest messages in the middle of the night that I definitely have to change mental gears to respond to. So I guess what I am saying is, I think she has gotten an impression that it's like the HD porn videos. That I will easily be able to do things like maintain an erection inside of her and pee. I HAVE done it with my first ex, but it definitely took practice. 

What would be your advice for when she comes over next week to make sure she enjoys her first time with pee play while having reasonable expectations? With the other two, I was in a relationship so there was plenty of time to talk about and work up to everything we did. Since we basically only talk about sex and dirty things, I want to make sure has an amazing time and isn't disappointed. For reference, she is the only person who ever pegged me, so we are pretty comfortable sexually. One note, she doesn't wear panties ever but knows I like them and would want to watch her wet them.

Thanks everyone! Feel free to DM me if you want to chat..  I'm actually holding right now and I don't really have anyone but her i can talk about this stuff with! 🤭