This is Keine Kamishirasawa, a 3rd stage boss, and extra stage mid-boss of IN. She is a school teacher, and a guardian of the human village. She seems to have a strong will to protect humans. She is probably the safest person to be around in Gensokyo if you're a human. She's also a resident of human village. She is a were-Hakutaku, her powers including hiding history, and create/changing history.
