He is a potential companion.

He is a powerful fighter. He is also supposed to deeply unsettle the player. Can pick locks.

He has a bright gold tooth. It gleams in any light conditions.

His body is covered in tattoos of eyes. Forehead is branded with an inverted cross. Perhaps has “ANGER” and “WRATH” tattooed on his knuckles?

He believes he is the reincarnation of Samael, An angel of destruction created by god to wreak vengeance on the world.

Depending on the outlook and precepts of various religions in which he is a figure, Azrael may be portrayed as residing in the Third Heaven.[2]:288 In one description, he has four faces and four thousand wings, and his whole body consists of eyes and tongues whose number corresponds to the number of people inhabiting the Earth. He is constantly recording and erasing in a large book the names of men at birth and death, respectively.[5]

Samael is described as the "severity of God"

Perhaps refers to the player as “sweet cheeks”?

He was a dangerous serial killer and sex offender, incarcerated before the war. When the bombs went off, the prison was partially damaged. The guards fought a running battle to contain the inmates for the next four months. Food ran out. Water and power were disrupted. In the end, he was the only survivor.

He lived a while off of the smoked meat of corpses before emerging to explore the world.

Widowmaker shotgun. Giant fighting knife.

[maybe constrain the sexually harassing lines only to male protagonists]

When the bombs fell there were over 2000 prisoners and 150 guards trapped in Singsing. Do you ever wonder why I was the only one to get out? Maybe you should.

When you die, I want you to know I’m not going to waste any part of you.

The war was the best thing that ever happened to me! Everygoddamn day I wake up and I’m in heaven.

I think I dropped some ammo behind you. Would you mind bending over and picking it up?

I can’t actually see these ghosts you’re always talking about. I’m pretty sure you’re imagining them. I just shoot when you do.

Why do you need to know my last fucking name? There are roughly ten people alive within a 100 mile radius of here! We are long past last fucking names!

You remind me of a guy I used to know. I shivved him soon as the bombs fell. He died crying, but I don’t think you’ll go out like that.

Hey, I found some kneepads you might like. You should try them on.

I’m not wearing any underwear. Let’s be real, you were going to find out sooner or later.

Oh this brings me back… [looking at disturbing locations]

In the seventh and final heaven Moses saw two angels, each five hundred leagues in height, forged out of chains of black fire and red fire, the angels named were named "Anger" and "Wrath”. It was they that God created at the beginning of the world, to execute His will. There was another angel in the last heaven, different in appearance from all the others, and of frightful mien. His height was so great, it would have taken five hundred years to cover a distance equal to it, and from the crown of his head to the soles of his feet he was studded with glaring eyes. "This one," said Metatron, "is Samael, who takes the soul away from man."

[muttered] They said, ‘Sam, you’re in danger.’ I said, ‘I’m in danger? I’m in danger? Motherfucker, I AM the danger.’

[in darkness] May the bodies I burn light my way…

[when dismissed] [I think it’s time for us to part ways.]
You think so, huh? You won’t last ten minutes out here. See you on the barby.

You’re probably wondering to yourself, ‘Is this guy the villain in my story?’ The answer is no. … It’s my story.

You ever wonder how I came through the starving times rocking a gut like this? A smart person would probably put a lot of thought into that.

Ghost of this… ghost of that… to me they’re all the ghosts of punk-ass-bitches who couldn’t hack it.

[trade]
Carry your shit? Seriously? You’re not even going to put up a fight?

[trade]
Huh. I thought I’d have to take it off your corpse.

[after combat]
What the…? Is this YOUR blood on me?

[after combat]
Hhahaha! You should have seen your face! You were all like ‘Ahhh! Help me, Sam! I’m too young to die!’

[taking drugs]
Hey! Save some of that for me, goddammit.

[taking drugs]
Hey! Knock it off. It makes the meat taste funny.