You wake up in darkness. You’re in a dark mansion, and a maid is standing in front of you. She calls you “the master of this mansion” and gives you a warm welcome back. You can’t remember who you are. The maid understands this, but as your servant she decides to help you recover your memories. She’ll tell you a few stories — stories about this mansion’s past. Once you’ve heard them all, you’ll naturally remember who you really are. The maid leads you to one of the mansion’s doors, opens it, and tells you what happened behind it.