He wonders why he's reflexively doing that and then he gets suspicious of the fact that that's not something he would do reflexively and even if he would he would still have stopped immediately on wondering about it and - no he can't shut up, no he can't just scream instead, no he can't raise a hand - it takes a while after that for him to think anything other than oh fuck oh no over and over.
He's been speaking modern English for a while, but his most comfortable language is Latin, and it's not even his first. He's got Old English, Old French, Classical Chinese, Cantonese, Japanese, Classic Maya - more than that, actually, so many languages he's lost count, most of them too rusty to jump back into without spending a while listening to someone else - and he hates it, hates that he can interface with the world in so many ways and all of them were taught to him by demons.
That's the most notable thing about him, is that either he's delusional or he died centuries ago during a plague epidemic, and since then he's been in Hell most of the time. They told him it was Purgatory, that he'd learn better and then go to Heaven, that while he was there maybe he could help them help others, too, for values of "help" that included "break their wills because they need to stop being so sinful" - he doesn't want to think about it and also he doesn't think he can ever forget, not the time he took the hand of someone he'd up till then called a friend and started breaking their fingers, not the times he ordered someone else to drag someone off out of his sight while he knew what was happening and relaxed -
- It's a lot but it's not definitely centuries. If it is centuries, then there are stretches of years eaten by sleep deprivation or blurred by sheer monotony. It's more than there really ought to be at his apparent age, anyway. And some of it's testable; he thinks he's not really alive, will never age, doesn't need food (he had that driven home to him particularly humiliatingly), heals from literally everything and often in under a day although there's some kind of extremely painful workaround for that (he didn't start out male, that was a reward or maybe a reminder of what he's done, one or the other).
It's a very good healing factor but it doesn't keep him healthy, he's weak and miserable and exhausted and fuzzy-headed and being stunned was the closest he's gotten to sleep in months. They dolled him up a bit when they sent him to Earth (to save people, they said, but he's pretty sure he's been damning them, actually) to make him look more vaguely angelic than obviously damned, but that's only the magic of personal grooming. He has long since forgotten that living people who feel this way have a tendency to fall asleep as soon as they're horizontal.
Someone will, actually, look for him, but not today, and not someone who'd call the police, and anyway maybe he's delusional and they won't. It's only been about a day since he decided to go to ground on Earth and hope Hell couldn't track him down. They weren't even going to check in for days yet.
Though when he manages to unstick his thoughts from sheer horror he supposes that actually they can just possess him, so that's fucking delightful, and it's also baffling but he's in no shape to think about why it's baffling. The most salient thing about it, at the moment, is that he can give up.