The scrapbook in game shows me that I have unlocked a few outfits that I do not own. The sci if fan and horror fan outfit are among them.

Same here. I think they just show up when you start a vault. I will have to try making a new vault and see if the same ones show up.

Well,

At least your dwellers arent changing out of armor into something more comfy, whilst out in the wasteland, or coming back to the shelter with pointy ears!