Sorry, but I can’t do that

I was chilling in the lowest level of Hell, being an above average demon.
I had no authority or power to speak off, but at least, I couldn’t be simply thrown here and there…at least not on this level.
I could eat beasts, and low level demons to sate my hunger and get stronger, and from time to time, I was summoned to different planets to sign a contract for juicy souls.
But this time…
This time I got something impossible.
A sacrifice of more than ten thousand lives, and the promise of a supreme soul, a future saint, archangel’s soul as final deal.
I wanted to decline it, but I couldn’t.
The summoner forcefully brought me over, and I found myself in a lavishly furnished palace hall.
“Oh, Great Fallen One, I came to make a Faustian bargain with you.
The souls you have gotten were just a gift, and here is the true item of exchange.”
An elderly man, draped in grandiose clothes, countless jewellery and walking with a golden crane said, as he pointed towards an almost naked young woman.
She was Holiness born into human flesh.
Long, golden hair with streaks of amethyst purple cascaded down over her entire body, that’s why I called her “almost” naked, even though she wore no clothes at all.
Her body was perfectly proportioned, as if sculpted in the image of the Ancient Succubus race or the Holy Thrones of the angels.
Her skin pale as milk with a touch of shade of honey like golden in it, and her green eyes like the freshest leaf’s.
Her lips were red as the night rubies of Hell, and her face was stubborn.
As a flesh and blood demon, this meant a lot to me, but not as much as what her soul meant…
It was simply, pure and overwhelming.
It towered in the hall like an ocean, threatening to drown me in its golden and silver waves.
“A future Saintess, even maybe Hero or Mother of God…”
I murmured.
“Indeed! A hundred million undead died in order to gain her, even twelve liches under my rule were sacrificed for her.
Now, my wish is simply, make me truly immortal, grant me the heart and body of a demon, and she shall be yours.”
He said.
I choked.
This will be awkward and painful for me.
“Sorry, but I can’t do that.”
I said, shrugging.
The elderly man stopped.
“What do you mean by that demon?”
He questioned.
Oh, he is getting angry, not that I cared.
“You read your tomes right, human, your sacrifice would have maybe even enticed a Demon God, let alone Lords, kings, dukes and all the princes who might have been able to grant thy wish.
But…
You botched the coordinates, and like an ape, you pointed your sacrifice to the lowest level of Hell, where only up to Generals gather.
No way a higher demon would have sensed your sacrifice lest they were constantly watching the lowest level, which, I assure you, they rarely do.
Each Hell is endless, so you were unlucky.”
I said chuckling.
“You demon! I shall imprison you, and torture out all those souls I have sent you!”
He said, magic circles activating all around me…before dissipating.
“Sorry, I might be an average demon, but I have a special constitution.
Magic holy or not, won’t work on me.
It’s not that good in Hell, since most demons have also sturdy bodies, but here?
You can’t do a thing to me, so…I shall take her, and leave, bye!”
I said, grabbing the holy woman by her waist, and leaving.
The elderly man’s roar shook the space, but he couldn’t do a thing.
I took the woman to a temple on this planet, before planning to leave.
“That’s all? Your lust filled gaze never left my body, nor my soul…
You won’t ravage me? Consume me?
You will free me?”
She asked, with a smile on her face.
“Sorry, but I can’t do all those things I want to do.
He might have been stupid, but I am not.
You aren’t chosen, you are a reincarnation, and I was already damned once, I don’t want to disappear, so byeee!”
I said, going back to hell.
I could swear, that damn scary yet hot woman licked her lips, murmuring “You won’t get away next time…”
I shrugged, no way she would come to the lowest Hell for me…