Why have I not seen this before? Even from the clips I found on youtube, I'm grinning -- Samurai Jack-style animation, filled with little details: Pangur Ban has one blue and one green eye; Aisling can't pass between iron bars (or into a monastery, most likely), so she sends the cat into the building, turned to knotwork under her singing, as a thread to lead Brendan out.

Also, um, problematic Vikings, albeit the story does need a Big Bad.