Came across this dialogue while reading Japanese writings online.
Boy 1: オタクにじみ出てますよ
Boy 2: 違うっつってんだろ
My Japanese beginner skills would translate it as "Your otaku-ness is bleeding out." But I'm sure that's not exactly right.
Also, I see a lot of ってん in casual dialogues like this. I'm not sure what that exactly means.