Original title is "Warum küßt mich dein Mund so heiß?" by Eric Plessow (Erich Ewald Walter Plessow) as "Pablo Lesso-Valerio" who also wrote the German lyrics as "Ewald Walter" in 1931. So there’s nothing "Spanish" in its ethnic, but "English", as it’s sung (beautifully) in this language.