Getting right to it, I lean heavily towards tentacle play and generally prefer to RP as mostly instinct-driven monsters. That's not all I'm willing to do, but it's my usual style. Sometimes I do RPs where the monster will swallow and digest the girl, which I don't write in a very detailed/gruesome way, but I understand if that's too much for you.
Here's a few more things I like that I should probably mention: Rape (though I am open to consensual sex, even with tentacles), mild cum inflation, tentacles traveling all the way through a girl's body, lactation (either milk or cum from having nipples violated), oversized insertion or multiple insertions in the same hole...basically, things can get pretty "rough" in my roleplaying. I'm willing to tone it down some if requested.
Things I don't like: Scat, gore, furry. I'm not very interested in "romance" RPs. And I'm not a fan of excessive use of "magic spells" and such (a little bit can be okay). That's it, off the top of my head. If you have any questions, feel free to ask me even during an RP.
Typically when I create an RP, I'll use a picture I found as inspiration and build the RP from there. I don't really use persistent characters/worlds, each RP is its own thing. Usually my settings are generic/original, but sometimes I'll use an established setting such as a game series. Pokemon is a great example. I'm comfortable writing in the first or third person depending on the RP or my mood.
I view hentai RP as kind of co-writing a smutty short story with someone, with neither player in full control of where the story goes. I do come with the caveat of not having much time to devote to RPing, so you may be waiting a few days between replies from me. I also don't reply on weekends.
Thanks for reading, I hope we have fun!