Holtor

Holtor is is one of the three of Luna's sibling, the failed attempts at creating "The Sun". He and his siblings guarded Luna's nano cells until Ringo arrived, they deemed her worthy and gave them to her. With that they were finally able to "sleep".

Physical Appearance
Hoto has the appearance of a small robotic humanoid boy with long pink hair and bright green eyes. He doesn't seem to be effected by the Ruin but has a long black line racing down the left side of his face spacing right above his eye but continues after. He wears tattered green clothing.

Personality
Holtor was a kind Robot who believed that the world belonged to everyone but still had a firm belief in protecting Luna's secrets, just like her siblings. He was semi trusting towards strangers, particularly Ringo, who he chose through his "True Vision" to obtain Luna's nano cells.

Casshern Sins
Hoto was built by Luna's creator as a project to mimic Luna's abilities. Hoto along with, Hoti and Holter were failed subjects, leaving Luna as the only Sun. When she was murdered by Casshern, the Ruin began and the creator died leaving the three to guard Luna's secrets.

A mysterious group of travelers arrived on day during one of Holtor's strolls with his siblings. He took a particular liking to one of the travelers, a small girl named Ringo. His siblings explained how Holtor's body is frail, so he cannot stay away from their home for long. They return only to find two other mysterious strangers where everyone seems trusting except Holtor. After they were forced to leave due to their obsession, the travelers returned and Holtor chose Ringo through his "True Vision", allowing he and his siblings to sleep and allowing himself to give Ringo Luna's nano cells.

Casshern Sins
17. The Glass Cradle