I just played through the DLC, and after I appeared in my apartment, I saw a strange reflection. When I scan the room, V is displayed. But it looks more like an evil two-face clone from the mirror world. He always turns his head toward V. After I leave the apartment, he disappears. In photo mode, he also disappears as soon as I deactivate the NPCs.
I can reproduce this by loading the save file. No mods, just the game & DLC.
Anyone have any idea who or what this is?