Should I tilt my DIY self-standing bookshelf backwards to prevent it falling down?
Use Screws Anyway
If it was me, I would quietly ignore &quot;I am not allowed to secure it using screws in the wall.&quot; We are talking about a couple of screws here, which would leave ~ 1/4&quot; holes, not cutting out large sections of the wall.
Assuming it is drywall or plaster over studs, as opposed to a brick wall, I would put in two screws (~ 2&quot; long) through brackets on the top shelf positioned so that the screws go into studs. The patching needed when you leave, if any, is minimal - really would get taken care of trivially as part of a routine &quot;get ready for a new tenant paint job&quot;. You'll sleep much better.