How much force would a slipper need to shatter glass from that distance?
How fast would Kei's leg need to have been moving to generate that much force?
@AgentKuga
It's a natural phenomena that occurs when two or more people spend prolonged periods of time together. They become easily entertained by the simplest things.
It's called "the Neanderthal effect" (probably).
From what I understand, calling them slippers probably isn't really accurate, the kind of shoes Japanese students wear inside school are probably closer to something like loafers?
It's not like she broke a window with a house slipper