The folklore says that if an object serves you 100 years, it will acquire a soul. This is how Shiin, Uro-Uro, and Jiro-Jiro were born. The names correspond to the nature of the holder.  Shiin is the silent one, Uro-uro is the one who would like to roam without noise and Jiro-Jiro watches viewers intently. You can see nuances of expressions in their eyes – they are playful, sinister, mischievous, malicious, and so much more.