Kozo Ryuzoji

is the mysterious antagonist and headmaster of Sakaimachi Academy in the series.

Etymology

 * The name Kozo means "happiness, good luck" (幸) (ko) and "three" (三) (zo).
 * Kozo's surname Ryuzoji means "dragon" (龍) (ryu), "warehouse" (蔵) (zo) and "temple" (寺) (ji).