Cloak Clasp of the Light Thief

This intricate cloak clasp appears to be a piece of extremely high quality jewelry.
The luck user of this clock clasp can, at will, vanish as per the spell. Additionally, when the user vanishes, a single illusionary double appears exactly where you are standing. If you move away, it stays put and it will interact with its surroundings minimally without moving. It will nod, make basic idle comments like, "Yes, yes", "No", "Can you say that again?"
Any physical interaction with the image will reveal its illusionary nature. The image will fade after 1 minute.