Evolution
Kai watched as the door opened itself, then frowned when he saw who was on the other side. Hido.
The scariest of the 3 headmasters. At first, Kai felt it was strange that he'd double as a teacher. Didn't headmasters have important duties or something? But he figured they weren't necessarily limited to just being one or the other.
Obviously, or Hido wouldn't be standing in front of him right now.
Staring him down, Hido raised his hand to stop his raven from flying to Kai. Then, he said, "You're late. The only time that is acceptable in this field of study is if your discovery is worth more than the missed time."
Turning around to walk back their the door, he said, "We'll see if you make such a discovery."