"I'll show you. This is what it means to kill something."
— Shiki, Tsukihime
"J-J-Jack! But they said you were dead. You must be — double dead!"
— Oogie Boogie, The Nightmare Before Christmas
"He couldn't be any more dead."
— Heat Man, In Wilys Defense
"Where do you go if you die when you're already in Hell?"
"Superhell. It totally sucks there."
"As Coroner I must aver,
I thoroughly examined her.
And she's not only merely dead,
she's really most sincerely dead."
"Nope. Can't do it. Sorry. I reeeeeally want you all dead. And not the kind of dead where there's a possibility you might still be alive. I want you SO dead, that you'll be reincarnated as a corpse!"
Krusty: Well kids, we all know that sometimes when cartoon characters die, they're back again the very next week. That's why I'm presenting this sworn affidavit that Poochie will never, ever, ever return!
Lawyer: This document conforms to all applicable laws and statutes.
The Simpsons, "The Itchy & Scratchy & Poochie Show"
"I will catch you. I will cut you down. I will bury you and plant a tree on your grave. My people will eat the fruit of that tree, not knowing it was sustained by your rotting flesh. They will tell me how good it tastes, and no one will never know.
I will erase you."
Freeman: (Looking at a dead soldier) So what's the story on this guy? Yep. Deader than a dead... dead guy.
Freeman's Mind, episode 11
"Malack's never returning. Neither's his killer."
Miracle Max: It just so happens that your friend here is only mostly dead. There's a big difference between mostly dead and all dead. Mostly dead is slightly alive. With all dead, well, with all dead there's usually only one thing you can do.
Inigo Montoya: What's that?
It does present a curious curl in the metaphysics, doesn't it? If you murder a monster in Monster Heaven, where does it go?
— Castiel, Supernatural