This is a small marron & cookie chocolate made by a confectionery company which is famous for Japanese children, also a part of adults.
As you know, it looks like the head of #6401 in the First Smile theme. However, this face slightly seems to be a sarcastic person with the bended mouth.
#6401 is discontinued and it may not be available, but I think you can get this chocolate in the whole country of Japan.