He was sealed up in a vase many millenniums ago by Prince Hamja, but Princess Cye-Ra, after Sabakunya convinced her he was a nice guy, released him. Then he imprisoned her in a tower and decided to marry her so he could be king of Hamja Kingdom. He has many magic armored henchmen as guards.
Hamtaro defeated him and re-sealed him by playing a song on a magic flute.
His name is a combination of the words sabaku (desert) and nya (the sound a cat makes, equivalent to "mew" or "meow")
See also: Sabakunya/Gallery