I know this has a lot of potential to be abused, but I think it would be interesting.
Basically, who do you think the above poster's arch nemesis would be, and why? It can be another user here on KYM, of course, but I'd rather use characters from fiction so as to avoid potential flame wars.
As the one who posted this thread, I'd have to say that KYM's nemesis is most likely 9gag, because those idiots over there stole our Holy Cheeto!