I'll meet you there || A Klaus x Dave story

Klaus accidentally travels back in time, he travels so far he made it to the era of the Vietnam war, as we all know he meets Dave, but what if he traveled back with him, What if he caused the apocalypse because of the butterfly effect?

Just a warning, I don't have a lot of time right now not to mention a lot of motivation. I really suck at writing so if this goes anywhere- idk how to feel.