Final Key

Original Form=

The spirit of a legendary key that has been sealed away for a very long time. No matter how stubborn or how unique the lock is, she will be able to release it and open the door. She is not only a physical key, but she can also unlock the doors to hearts, so it's not possible to keep secrets from her.

How to Acquire

 * "Ayakashi Quest" event: Collect all six Final Key sealstones. The sealstones will only last for the whole duration of the event. Limited
 * You can also obtain her magatama by completing the sealstones again for the second time and onwards.