From Aozora Wiki
Ball-Kun (ボールくん, Bōru-kun) is a character in the Aozora's Adventure series.
Much like his counterpart, Paku-Chan, Ball-Kun is designed with the same metallic body and limbless body parts. However, there are several notable differences. Ball-Kun's main body is a full circle, unlike Paku-Chan's, which is slightly taller. Ball-Kun shares the same LED screen as Paku-Chan, which is used to display emoctions, but is made of red LEDs as opposed to blue. His spherical hands are also a different color.