So if you find one of these in a room, bag, bathroom drawer, or jacket pocket, the most likely answer is simple.
It is a nasal inhaler stick.
A little menthol-scented breathing aid.
Not a secret USB.
Not a strange device.
Not something to panic over.
Honestly, I felt a little silly after finding out what it was. I had spent all that time imagining the worst, and it turned out to be something people use when their nose is stuffy.
Still, I can see why so many people would be confused by it.
Without the box or label, it really does look like a mystery object.