Naoyuki Andō (安堂 直行 Andō Naoyuki) is the childhood friend of Hiro Shishigami who acts as Ichirō Inuyashiki's informant and assistant after he finds out the true nature of Hiro and help him in his quest to save people and hunt Hiro down, even as far as teaching him the basic of how to control his mechanical body.
He's a big fan of Gantz manga series
Andō is a man of average height with long brown hair that covers his forehead and brown eyes.
- The name Naoyuki means "straight" (直) (nao) and "to go" (行) (yuki).
- Andō is a big fan of the GANTZ manga series, the manga that was created by the same creator of Inuyashiki
- Kanata Hongo portrays Naoyuki Ando in Anime and the Live Action adaptation of Inuyashiki.