Imma go with Monsterization since it have a lot of varieties

As with Demons as well (Elemental Demons, Yokai, Demonic Dragons, Alpha Demons, Hellspawns, Ascended Demons etc.)

Second option

But every demon is a monster but not every monster is a demon. plus term monster is more broad then demon. i can turn someone into monster who see the future but turn back into human if heard bad dad joke.

Demons are more intelligent and sneaky

Bc many of them are just vape smoke.

Monsterization