Posted in time for locktober, this would be a great addition to the season! This key lock allows you to lock most size keys, keeping it from being used by tempted (and horny) hands. The case is small but durable, and the holes are able to align with the key hole so you can slip in a padlock, a disposable lock (https://www.thingiverse.com/thing:4607130) or a zip-tie. You can also slip a necklace chain through it and wear it around your neck!

The Key: https://www.thingiverse.com/thing:2765430. It isn't included in my file.