Crusade captured Azazel
There was a Crusade episode (B5 spin off series) in which they discovered an alien that could transfer to others by touch. Crusade,S1-E8 "Appearances and Other Deceits"
At the end they tricked him into a body he had no place to escape from. Good episode and perhaps the end of Azazel. Thought about it while re-watching Fallen. It was interesting to which Fallen then Crusade s1e8.