These little mini-treats, known as ブルボン プチ, or Bourbon Petite, can be found at most stores in Japan. There are tons of flavors, but usually are some kind of little cookie. Here’s their website to learn more about these delightful little guys: Bourbon Petite
Their mascot is this little bear guy:
Each little treat is pretty small:
They are great quick snacks, and really cheap. I enjoyed the mini-chip one, which tasted a lot like Pringles.