A Shadow of the Past

Exploration Stage: South Fort
From: Mr. Black
Description: You solve mysteries, but you won’t handle mine. It will remain under lock and key in my file cabinet. But now I feel like telling you something important. My tie pin... Where did it go? I can’t lose it, it’s crucial. Help me find it.
Completed: I appreciate you retrieving my tie pin. I wear it as a memento of that girl’s mother. The child clearly inherited supernatural powers from her. So, the girl’s mother isn’t the Marquise but a witch! But I didn’t realize it right away...