For those two weeks we called him Puss or Puss in Boots, because he would sleep in my fiance's work boots. He was also sometimes called Little Devil or Lil' D (from my fiance), because he got into EVERYTHING. I considered Loki, but eh... wasn't right for him. So I played around with Devil-like and Trickster names from Mythology and I came up with Sathan. :) We call him Sath for short.
{The name is pronounced: Say-TH-ann}