In addition to shaking his world-view, Keiki's encounters with the abnormal have led him to conclude that neither Sayuki nor Yuika are the elusive Cinderella. Through process of elimination, the only one remaining is Mao.
"Come to the Shodo Club room immediately."
"Y-Yes ma'am!"
"Come to the Shodo Club room after school."
VENHA JÁ PRO CLUBE DE SHODÔ!
SIM, SENHORA!