This is Sugar. His hero name is K9. He was born a small dog but due to an unknown (at this time) phenomenon, he's able to take on a human form while keeping his dog abilities. Sugar is small, adorable, and innocent. He's still learning about the human world, so he's childlike. He's best friends with another main character, Zackie, whom he sees as an older brother. As for his voice, refer to the clip I posted above.