As the title suggest, I'd like to read a novel where the MC wears a full suit of armor (with the helmet covering his face), if not that, a hooded cloak, a mask, or anything that prerry conceals him/her will work, too. It'd be great if such an attire lasts for a large portion of the story, not just in a single arc or less. Feeling edgy right now. It can be a novel, manga, anime, or live action.
Delve The MC gets a really powerful suit of armor tailor (blacksmith actually) made for him... he becomes too paranoid of everything and lived inside it for quite a while. WARNING: This god damn story has a lot of math.
Not fully suited all the time. There is omni-magician, a transmigrator magician who ripped off iron man to make a suit with jarvis included