Revenant folders on my Nexus 7 (flo) - how to track down the culprit? This may have been going on for a while, but I have only noticed a few weeks ago.

There are some folders inside the Downloads folder (i.e. subfolders and subsubfolders) which originally contained documents meant for a particular period and thus were named after year and month (e.g. 2014-05).

They contained documents which I have read in apps like Moon+ Reader.

I deleted those (sub)subfolders many times now, but they keep coming back.

My first hunch was: "oh, somehow Moon+ Reader must have registered them in its DB and keeps recreating them". So I decided to use the rudimentary file browser included in that app and removed the folders there. Yet, after every reboot they keep reappearing.

How can I track down the culprit? Is Moon+ Reader perhaps known to behave like that?
I have now been able to confirm without doubt that indeed Moon+ Reader is responsible for the folders reappearing after deletion.

The problem is that I've come up empty-handed when looking for a database or text file related to Moon+ Reader which contains the names of those folders.

Meanwhile I have moved my books into the Books folder instead of leaving it in a subfolder of Download, but now the whole folder hierarchy inside Download which was used by Moon+ Reader keeps reappearing.

Unfortunately even rating the app requires a Google+ account which I will not create and there is no support contact given. So no way to report this issue back. But I am thinking about extracting the app and trying to find the offending code to add more details here.