Is your D20 being naughty? Put it in the corner and make it think about what it's done with this duncecap diorama. Is it early intervention, or a die's entry to the school-to-prison pipeline? I hesitate to speculate about the imaginary metagame universe in which your dice live to serve you, their master and their god.
Get your die scared straight before it turns to a life of mediocre attack rolls and critical failures. Start a simple display of shaming with just the stool and cap, or go all the way with the classroom corner. The classroom corner includes pockets for the legs of the stool which can be press fit or glued in place, depending on the tolerance of your print.
You shall not share, sub-license, sell, rent, host, transfer, or distribute in any way the digital or 3D printed versions of this object, nor any other derivative work of this object in its digital or physical format (including - but not limited to - remixes of this object, and hosting on other digital platforms). The objects may not be used without permission in any way whatsoever in which you charge money, or collect fees.