@Heron2001:Koeie -
No Problemo - it's an Americanism...
Not going for the male/female or even proper.
Don't know where it came from - probably some comedian during the 1950s or 1960s... with the influx of the Spanish speaking population in major cities in the US.
It also pertains to the addition of "-o" to the end of words in order to make them "Spanish" for comedic effect:
"Where-o is el bathroom-o?"
Yet another Americanism rooted in our bull-headed refusal to actually learn more than one language.
(Aber ich versuche einen Ausnahme bekommen.) ;)