It's just occurred to me...Bob is a fake gamer girl thot born into a fat, diabetes ridden man.
Stay with me here. Bob only knows one pop culture nerd thing moderately well (Mario). He knows next to nothing about any other nerd thing. When he tries to talk about it, its filled with obvious errors that even the most cursory nerd fan knows is wrong. He pimps that one pop culture nerd thing so people think he's the real deal.
The problem is that gamer girl thots are hot and everyone thinks they can fuck them for some reason, so they get a pass. Bob is a obese man, with diabetes with the same intelligence level as well as level of morality. He confuses everyone, wondering what his deal is.
He is what happens when a gamer girl thot just happens to be a man. A very ugly, very dumb, very fat, man.