What You Need to Do
In order to talk to the ghost, you need to buy a mask called “Second Skin”.
You can get it from the Veiled Maiden in the City of Erlim after completing Lady Annika’s quest!
After you buy the mask from the maiden, you can talk to the ghost and she will lead you to a secret boss.
Important note to use both eyes
You use both eyes to to unlock the third and final ending boss. You just need them in your inventory.