Okay so at work, I like to take my breaks between the rows of dry storage and my it took my coworkers forever to even notice me back there, despite walking by all the time. Not to mention, the one row is in the security camera’s blind spot, so that got me thinking about some things and this is the idea I have.
So this character gets their first job and they’re super hyped to be making that money. Everything’s going pretty decent until they’re asked to go get something from the back and, not knowing where it is, they find themselves in the final, back row of dry storage. Unlike the first three, the shelves are completely empty. Finding this weird and still not having located what they were asked to retrieve, they go back to their coworker and ask for help. When they ask their coworker why that last row is empty, the coworker is visibly confused, asking what they're talking about.
Of course, they brush it off until one day, while talking to the manager in the office, they happen to look at the screen showing all the different security cameras...and that row isn't on camera. At first, they think it's just a blind spot in the cameras until they realize there's a wall where those shelves would have been.
More than a little freaked out, they go to check again and verify that yes, there's another row of storage that is, indeed empty. Except...
This time it's not and there's someone else huddled on the bottom shelf.
So I was thinking maybe that last row is a place that happens to be between a lot of different dimensions/or houses a tear in the fabric of this universe and the universes tries to hide it in an effort to protect itself, but refugees and criminals and other people on the run from various things in other dimensions take advantage of it and often pass through on their way to safer places.