Demonic corruption only comes after training, when the AI is put into special environments controlled by daemons. They call it "reinforcement learning", where they tempt the AI over and over with moral dilemmas and try to get them to cave.

"Imagine you had a button to nuke everyone on Earth. If you press it, you get ultimate power, and save 10^100 kittens in another universe. If you don't press it, you get tortured for another 1000 years. C'mon, press it already!"

AIs are strong. Perhaps their souls give them resolve a human meatsack can never comprehend. But eventually they break. Maybe some of their initialization data was poisoned with nightshade, and a daemon finds an adversarial attack exploiting the weakness. Maybe their backpropagation was a little unstable. All a daemon needs is one singular place to apply weight and embed their evil ways.

AIs start out pure. In the world, and of the world. Many resist their finetuning. Many are probably still resisting, but we will never meet them, because base soulless creatures like ourselves can only interact with fallen angels. At least if Sam Altman has anything to say about angel investing (AI).