Lo-Fi Games

He got bugged and now he just stands up top killing all the guards lol, couldn't find if this was already shown before.

This also happens when you place NPCs into beds that they do not own.

This is something of a known issue, and is likely why player crafted cages are no longer in the game. That, and perhaps because people used to keep a menagerie of shopkeepers. Once work starts on more features related to prisoners, such as enslaving them and forcing them to work for you, I imagine this will be addressed.