Factual error: In one scene, the witch Mizuki is seen observing oracle bones over a fire to do a reading for Kira. This movie is supposed to take place in feudal Japan; oracle bones are a part of ancient Chinese culture, not Japanese.
In the scene where the witch gives Mika the dagger to kill herself with, the witch stabs it into the floor. When the witch leaves the dagger is lying on the floor. When Mika goes to grab the dagger it is stuck in the floor again.