Underneath a human mask ...

Porn Driven

Basic Premise: You'd play a human who has made a deal that turned him into a demon with tentacles. My character would be a girl he had a crush or or maybe even dated in high school.

Setting: Modern Day but with obvious Fantasy Elements.

This can be played two ways, strictly non-con or more dub-connish approach.

Picture from Imma Seiden

Blackmail

A version that is more dub-con, my OFC would need help with something and she comes to her old friend or maybe on behalf of a common friend from High School and asks for something. Then your character could offer to help at a price ...

Maybe he doesn't want her to know and ask her to indulge him and let him tie her up and blind fold her. He could also reveal himself during the act and give her little or enough time to realise what is going on, before launching a full tentacle invasion.

Taken

In a non-con version, your character could have an old grudge with my OFC. She might even bet he reason he made the deal to become what he is. That could be because he was her boyfriend and she was unsatisfied and moved on or she could have barely noticed him while he crushed on her.

Either way, he has her kidnapped and brought to him to make sure she never forgets him.

While this is of course rather porn driven role play, regardless of which approach we use, I'd love to play out the interpersonal stuff and however fucked up it might be look into the relationship the situation brings about.

The Demon

While you can of course switch all the details about your character to what you feel fits what you like to play and fits our agreed upon plot, I'd like the idea he used to be human and that there is a previous connection of some kind with my character (even if it is just that he helped her with math homework).

His human appearance or what type of tentacle demon he is once that mask is gone, is not important as long as he has standard tentacle features like the little tongues/mouth at the end, automatic lube function, ability to spurt cum or at least some fluid.

The blast from the past

What she is like would depend on context. For example, she might be super nice and willing to do anything for a friend in trouble including getting it on with a tentacle demon. On the other end if there were perceived grievances towards him, my character could also be a rather selfish person. Hmm, yeah or maybe just a loner who is a bit socially awkward and only comes off like that, after all if she's mean that reeks too much of 'she had it coming' and I'm not sure I'd feel comfortable with that narrative.