You were walking through a hallway, when your friend Inosuke told you:

—"Uh, the Chemistry Lab is on the second floor."

Chemistry Lab...? Eh? Hold on a second. Oh, no. The first period today is... Chemistry. You go to the second floor, and take a peek at the Chemistry Lab... You see Professor Iguro writing chemical formulas on the board. Your seat was empty, since you were LATE.

—''Tch...''

Said Professor Iguro, frustrated.