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.
There has to be love there!
So etwas darf man nur machen,
wenn man sich liebt!
¡Tiene que haber amor ahí!
Tem que ter amor!