|Light Novel Debut||Volume1 Prologue (mention)|
|Manga Debut||Clock 1 (mention)|
His full appearance hasn't been shown so far.
He is a genius clockmaker, capable of rebuilding the dead planet into a clockwork planet. He is the creator of the Initial Y-Series, said to be the maintenance machines for the planet, though it is said to be wrong by RyuZU.
30 years after the Earth suddenly died, Y announced to the world that he can rebuild Earth into a clockwork planet using his blueprint. After he completed the clockwork planet, he designed and developed the Initial Y-Series, a series of highly advanced automata who excel at one or more aspects.
A retired mechanic claimed that Naoto is actually "Y" himself at the end of Chapter 24 (Manga)
- Information will be added when it is available.