Look at this device that lets you insert an infinite number of books into a finite bookshelf

中二の時に作った割とどうでもいい発明品出てきた pic.twitter.com/ugk05vKITW— 双子座症候群@YellowEyes (@PFgeminiman) December 13, 2021

Having trouble stuffing another book into your overstuffed shelf? Just use this nifty gadget! They probably sell them at Mandarake.