It is a silver lock specially built for Diva's cell in the tower. It is ornated with two mirror symbols of gold - each consisting three feathers and an open claw. The lock used to be opened only by Amshel who looked after Diva. But during Joel's 72th birthday, Saya manages to procure the special key to the lock and opens it. It's left on the floor in front of Diva's cell after Saya leaves to answer Hagi's call.