Benimaru's looks and a number of his special moves are homages to anime characters.
His Three-Stage Reflex Kick and his Phantom Hurricane super come from Polymar.
His Flying Drill kick and Raijinken come from Casshern.
And obviously his appearance is very similar to Polneraff from JoJo's Bizzare Adventure.
Ironically, despite the references to anime, he hates anime and otakus.
That's intentional on SNK's part.
Other anime references in SNK that I can think of off the top of my head:
Athena (the Greek Goddess, not the schoolgirl idol) = Athena from Saint Seiya.
Ryo Sakazaki = Ein, the Bounty Hunter from Fist of the North Star 2.
Geese Howard = Souther, also from Fist of the North Star
Andy Bogard = Shin, also from Fist of the North Star.
Mr. Big (Art of Fighting) = Umibozu from City Hunter.
I'm not even kidding about Ryo. He literally looks like Ein. Go watch it if you don't believe me.
What's even funnier is that Casshern and Polymar made their first ever appearances in a fighting game (Tatsunoko vs Capcom) long after their actual special moves did, with the introduction of Benimaru in KoF 94.