It happened to me a couple of times. One time I was fighting a dude on a cliff-side outside the monastery but when I performed the finisher we were inside the monastery, and then once it was over I was back outside under the trees with graves all around. I figured it was just because all the finishing animations are canned, and have to be performed in an area with sufficient room, and since there wasn't enough room outside it put me in the closest available area, which just happened to be completely different. *shrug*