This is Krishna crawling with a ball of butter in his right hand. He is protected by a seven-hooded cobra.
This scene depicts one of his mischiefs. Being fond of butter he steals butter and runs away from his chasing foster mother Yasodha.
This idol is only 5 cm in height and a lot of work for a bronze of this size.
Given the alloy composition and the casting quality, this is most likely from Tamil Nadu. Crawling Krishna is a regular feature of Vaishnavite household altar.
This probably dates to the nineteenth century.