I live in Texas on the Mexican border, in a large community where Spanglish (or "pocho" in the local vernacular) is more predominate than English as language.
We're close to the Gulf of Mexico here, and I fish there a lot. There's a sub-community of fishermen who see each other a lot at the docks, launching and recovering boats and displaying/bragging about their catches.
Its common for folks to poke fun at each other regarding their boathandling and fishing skills, while bragging about their own.
"culero", or, rather, "Captain Culero", is my nickname with several of these folks. They gave me this affectionate tag becaue of my sweet personality and disposition, which I routinely display towards others there.
Its slang for "prettythanghole" locally (Spanish speakers worldwide have several different dialectic slang uses for this word, but that's what's prevalent locally along the Tex-Mex border).
culero (really a nice guy, trust me
)
PS - I actually own a boat named and labeled "SS CULERO" and had it for a long time before I found Air Warrior and needed a handle.