Ejecting Drive

If I connect the TAINER via a USB cable to a Windows computer, I can see the folders with my backed up files. After I extract the files, I don't want them on the TAINER any longer. Is it appropriate to just delete the folders that have the photos? Is there a problem if I delete other folders that TAINER created? And more importantly, the TAINER is connected as a permanent drive (not a removeable drive), so there is no "eject" option. Can I just disconnect the USB cable after deleting files, after a short wait, without damaging the drive?