Endou Kaori

Known as the "God of Disguise, no-one knows Kaori's face or age, as she can change her appearance and voice easily. A person can even be a telephone pole or a mailbox.

Hobbies: Disguise, teasing, sexual harrassment
Special skills: Disguise, persuasion, acting

Spoiler

Kept a secret treasure hidden to protect the students, because it was cursed and would kill anyone who went after it.