I've watched an anime movie a few years ago where people are turning into monsters (because of inbalanced magic?). The main character hunts them with the same magic and wears a suit of armor that compresses his body to keep him from turning into a monster himself. I could have sworn it was call Steins;Gate, but it turns out that it is not. Any ideas?
I think you're looking for Strait Jacket, (2008).
In a world where sorcery and science co-exist, the power of magic comes with a price: Humans who do not take proper precautions are transformed into horrific demons. Those who destroy these demons - and run the highest risk of all - are tactical sorcerists known as Strait Jackets.
It was shown as one of the Sci Fi Channel's Ani-Monday features.