Cheek Pouch is an ability generally held by certain rodents.
In Battle Use
Animals with the Cheek Pouch ability are able to heal some health regardless of the berry they're holding when the berry is consumed. Berries of any kind are able to heal these animals in addition to their usual effects.
This ability may have been derived from how rodents are able to store food into pouches within their cheeks; thus, allowing them to store and carry enough food for when needed.