There is a cage with an axe in it above your house to show that you are an artisan. All of the artisans have to have this special sign somewhere near where they live to show they make things.
Artisans have to be marked this way because the Shougun (しょう) says so. The Shougun doesn't want to have to put any effort into finding people to make things for him, so he created this new system.
Currently there are no similar looking kanji which exist in the WaniKani learning system