culero means asshole, THATS IT. its as simple as that. goddamn of the people who defined "culero" in here knows what it fucking means? its not complex.
spanish-
guy 1- "ey me coji tu vieja guey"
guy 2- "te voy a matar pinche culero!"
translation-
guy 1- "yo i fucked your girl"
guy 2- "i'm gonna kill you fucking asshole!"