Recorder and Randsell is the story of the siblings Atsushi, a young school boy who looks like a grown man, and his sister Atsumi in high school who looks like a small kid. It follows their comical and absurd life.

Recorder and Randsell is the story of the siblings. Atsushi a young school boy who looks like a grown man, and his sister Atsumi in high school who looks like a small kid. It follows their life and the comical complications that their distinct looks cause for them and the people around them.—Niklas Zenius Jespersen

On the surface it seems as if Atsushi is an adult, but really he's just an elementary student. However, he is paired with a second-year high school student Atsumi, whose height is just the opposite of his. These two together create an unusual relationship and will undoubtedly instigate some comedic antics in this slice of life comedy.—Crunchyroll