Bunnariums are born with a wind chime either clutched in their hand or inside of their bodies. In some situations, baby bunns are born with multiple wind chimes. These wind chimes allow the bunns are able to interact with things, albeit invisibly, in their arium.

Baby bunns (otherwise referred to as kits, kids, or children) have fully formed ariums in their bodies but it is possible for the number of ariums and arium types to change as the bunn grows older. 

Bunnariums is set in a fantasy world, where modern technology such as phones, trains, and computers do not exist.