As he assents, the pain vanishes and Ty finds himself sitting in a plush armchair next to the same woman he had seen before, though her attire had changed. She was now wearing a more modest dress with images of chains on them.
"Now, I'm very sorry but your body will need to go through some fundamental changes," the deviless said "Human bodies are not supposed to host a devil, so I'll need to make it closer to what my body is like in order to allow it to host me. Good news for you is that this means you'll also be gaining additional abilities."
"How much control will you have of my body once we're done?" Ty asked
"That's up for discussion," the deviless said "Most who deal with my kind prefer to control their body for most of the time. What I propose is that I set up this mind space, and we alternate days. I control your body one day, and you control it another. We can maintain mental communication throughout the day. If we need to switch, then we can do that on a situation by situation basis. While asleep, we will both be in this mental space, so we can get stuff done during the night. Is this acceptable to you?"
Ty considered for a moment. It wasn't really what he was expecting to play, but he supposed playing a possessed Paladin might be interesting.
"Sure, sounds good," he said "So how much will you need to alter my body to contain the possession?"
"Alot," the deviless said, giving him a sympathetic look "You'll need to be female, for one. And I'll probably need to pour my essence into you to grant you my abilities. That should not be a problem, it will merely make you look more devil-like, like the tieflings of your world, and probably will add some chains permanently to parts of your body."
A magical rendering of Ty's body appeared between them, showing the changes. While Ty kept his hair and eye colour, his hair was now mid back length, he had a pair of small horns on his head, and he had a pair of wings made from chains on his back that didn't look like they would be able to fly. The rest of his body slowly reshaped itself as they discussed what he should look like, until him and the deviless were both satisfied.
"What is your name?" Ty asked
"N'Karait," she said "But I suppose you can call me Kara. And take that name for yourself if you wish to be called that since you will now be female."