Never once watched the anime. I've heard good things but I never actually took the time to check it out. Even though it pretty much checks all the criteria of things I like. Swords, cute girls, supernatural beings, etc.
My wife pulled up Netflix and this was the featured film release. So naturally she forces me to watch it. It was actually entertaining and had a bunch of sweet swordplay scenes. I'm sure they'll release another film since this one left a few things unanswered.
Perhaps now I'll check out the anime.