In a land of idiots, surely a wizard could prove to rise above the mind numbing levels of humanity's ignorance. But in Rosario's case, calling him a brain-dead idiot would be a compliment.
Rosario is the downright wacky, weird, and in truth powerless wizard/aid to The King. Rosario is in fact the smartest out of the brainless batch of bad guys that continue to hunt after Mink and her friends. But that's not saying much considering Rosario is virtually useless.
With no magical powers whatsoever, Rosario makes himself "look cool" by talking deep, entering with a bucket of dry ice, and supposedly being handy with poisons and toxins. Rosario was supposed to capture Mink and hold her hostage so that Ruth would hand over his wife's dragon hand in marriage to The King, but "accidentally" shot her three times with poison darts, and yet Mink survived and escaped, so now Rosario and The King are after her.
Rosario was the one who suggested planting Mink into the World Killer Martial Arts Tournament, which of course The King took all the credit for. Just to make sure she lost, Rosario even tried using an ex-lax potion and a paralyzing stinger bee to finish Mink off, but the ex-lax ended up giving Dick Saucer the runs, and his stinging bee worked but Mink's luck was apparently larger than Damaramu's (her opponent) brain. Mink eventually won the tournament.
Powerless or not, Rosario's cheap brain-dead theatrical tricks are sure to give Mink a run for her money, if not to make her laugh at them. Together, Rosario and The King hope to make Mink's life a living hell, even if the same happens to their lives in the process.
(source: Absolute Anime)