DEMONstration (Patreon)

When I was drawing this I kind of felt like there were tests done on humans with demon blood.

They were aiming for more aesthetic results; some of the test subjects would have limbs turn demonic and that wasn't good for a house servant so those would be used for soldiers or miners or more hidden work.

Some would go crazy and those just had to be terminated.

Maybe humans were chosen based on a lottery or something. So when the letter arrived you had no choice but to go - they probably didn't entirely know what they'd been chosen for - some generic 'you have been chosen to serve your country'. There's rumours going around after a few escaped and made it back to their family tho it wasnt long before they were terminated.

Prompto's changes makes him the perfect result. Skin glistens in the light and only a very minor demonic protrusion. The subjects usually gain  superior strenght and sometimes more special/magical abilities.

Prompto hasn't realised that change yet.

The emperor makes sure that all the best subjects are sent to him to be put to work in the palace, just another show of Niflheims power and advancement. The emperor especially favours Prompto - whenever he travels Prompto is brought to wait on him.

I feel like Prompto is the exact same personality wise but the emperor does not approve of his playful witty persona and wants emotionless, obedient servants. Thats taken a bit of training (read: punishment) for Prompto to follow.