Run.

These "run" comments are getting kinda boring now..

Would you say it's a running joke?

You should be scared. Run far away.

I don't know if you should be scared by that. It was just something silly to say

Maybe it's just a new video game. Like Half Life, but just After Life. But either way- run!

The only thing you succeeded at was giving me aids cancer

That's sweet :) He believes you'll make it to Valhalla, too!

Witness me!

Maybe he was joking around and forgot to explain his joke? I don't know what else to say

Seems likely

Or do you both have a class where they're talking about the afterlife or death or something during that class?

I don't watch Supernatural but it sounds like something that someone in a fandom might say? Like you say, a reference to something?

You should probably ignore that and get to know him more, if he is really as creepy as this. Then run really fast OP

For what? Ask him if he wants to plan your next reincarnated forms or something. Tell him you dont wanna be a cockroach again.

Don't freak out. That's completely acceptable if he's a Viking.

So it was all good except that one thing? Let that one thing go. If meeting in the afterlife is really something he feels strongly about, then unless he's a jerk about it maybe you could take the opportunity to enjoy having a friend with a different perspective. Broadens the mind.

I doubt he was being serious.