Blood Bow, unlovingly called Wilted Bloom due to their similar appearence to Apple Bloom, is seen by most of Canterlot High as a dangerous character but no one is brave enough to stop them... they carry knives everywhere for crying out loud!
So what happens when a unhinged person wanders through a statue by accident and ends up meeting their counterpart as a pony? Chaos... lots and lots of chaos. They are both unhinged, what do you expect?