"You got what it takes huh?"-Shadow, referring to Nero.
Shadow is a KM-ian who doesn't look like his kind easily being distinguished by his human-like form. He likes solving problems and figuring puzzles but dislikes social life, a similarity with his host Nero. Also has two distant siblings namely Silver and Hero who shows later in the series. Since meeting with Nero, he along with Nero always play chess to kill time. Even though his race is the highest rank so far, he dislikes his own kind because they seek power and lacks cooperation in which he stated when he and Nero are opening up.