“Found this skin in my wardrobe, on top of a piece of clothing. There was a live bug too: it m

“Found this skin in my wardrobe, on top of a piece of clothing. There was a live bug too: it moved relatively quickly in the style of a millipede or silverfish. What is it? And do I need to get rid of them?

Thank you very much for your help!

-H.J.“

Based on that photo I think it’s a Black Carpet Beetle larva or shed, comparison photos here:
http://bugeric.blogspot.com/2014/11/black-carpet-beetles-attagenus-spp.html 

Weirdly enough, I couldn’t find much information on them in Japanese at all, I wonder if they are widely known?

These are quite common across Japan especially in older apartment buildings.The good news is that they are largely harmless, the larvae feed on dust (shed hair and dead skin dust, etc), though in large numbers the larvae’s shed hairs can cause irritation on the skin, and they may eat organic things like wool or paper. They are easy to control with deep cleaning (closet corners etc. are a favorite haunt) though they are one of those insects that live closely with humans and for the most part, remain undetected and rarely cause a real problem. I see them individually once in a while, but I think my jumping spider population deals with them ;)