That one-swing wonder is pretty much curtains for everybody. Sort of a welcome party, if you will. If you had miraculously managed to pull off a victory there, you would have been cutscene-KO'd by the next guy. Death is inevitable in the tutorial level.
Most demons do indeed have red eyes, but if you find someone early on that breathes like Darth Vader and doesn't have blue eyes, you will probably regret visiting him.
--
It's a sad thing that your adventures have ended here !!