Sarah

Grandmother is a high ranking human at the Grace Field House, serving as its leader, who considers Izabella as one of her pawns.

When Sister Krone told her about the escape plan of Emma, Norman, Ray, Don and Gilda, Grandma told Krone that she would leave it all in the hands of Izabella because she is important to her and above Krone in every aspect.

She serves the Demon Boss.

History
She was the one who found out how Izabella was climbing up the wall.

Trivia

 * It is unclear if Grandmother herself was an orphan or not in the past.