That may be the song I hate the most on planet Earth.
. . .
Yes, I'd rather listen to Eminem rap. I'd rather listen to Inuit throat-singing (which is actually pretty interesting). I would rather listen to the recent hit song by the North Korean dictator's — er, Supreme Leader — rumoured mistress, a married pop star who climed the DPRK charts with this little toe-tapper entitled "Excellent Horse-Like Lady".
I assume something got lost in the translation; it's probably high praise in that language/society to say someone works like a horse, or has the disposition of a horse, or something along those lines.
Still makes for a pretty funny and easy joke, though — which is exactly what we specialize in, around here.