Apparently, if you got the Golden Claw, then it's a bug as well. It's intended to give an Elixir. And when I stole from him, it just vanished.
(You also forgot to put up my 1st bug too!)
Another bug:
Skills: Scorch, Frigid Touch, Nova Impaler
Desc: Apparently don't work on Monster-type enemies. ('Must target organic units.')
Sorry I understand what you mean now, I got the same bug as you actually, no item on steal. ADDED (Skasian)