TV-Series
Description
Cain Arisugawa is a central figure whose actions and ideology serve as the catalyst for the main events of the story. He is the original creator of the Mind Trance system, the revolutionary technology that allows a human consciousness to be transferred into and pilot a large robotic body known as an I-Machine. While initially known as a brilliant scientist, his true nature is revealed to be far more complex and morally ambiguous.

In his original life, Cain Arisugawa was an arrogant and egotistical man, consumed by an obsessive drive to gather data and advance his research. His intellect was undeniable, but it was coupled with a profound lack of regard for human life. This callousness led him to develop a plan of staggering scale and cruelty. To study and control both a rare mineral called Orichalt and the wandering planetoids known as Rajeev, he was prepared to intentionally sacrifice ninety percent of humanity. His research also involved unethical human experimentation. He used a terminally ill girl named Alice, the daughter of his colleague Jennifer Record, as a test subject, transferring her consciousness into Orichalt to create an entity known as an Orillian. These actions were not born of malice but from a detached, almost clinical pursuit of scientific progress, viewing everything and everyone as variables in his grand experiment.

Cain's role in the story is that of a hidden prologue, a ghost whose legacy defines the present conflict. His true identity is a major revelation, as it is discovered that the protagonist, the amnesiac excavator known as Ido, is in fact the consciousness of Cain Arisugawa. After his colleague and longtime friend, Addams Forte Chevalier, discovered the true extent of Cain's inhuman plans and his intentional sacrifice of Alice, Addams was driven to action. He used an intentionally flawed Mind Trance to forcibly transfer Cain's consciousness into an immobile I-Machine body and erased his memories, effectively imprisoning him. Addams then stole Cain's original human body and assumed his identity, using his reputation to build a powerful corporation.

Despite this, Cain had a contingency plan. He had secretly arranged for a specially designed I-Machine with no identification data to be delivered to his location. This vessel, designated ID-0, would allow him to recover his consciousness and escape his prison, albeit with his memories lost, leading to the birth of the character Ido.

The key relationships in Cain's life are defined by his betrayal of those closest to him. His relationship with Addams Forte Chevalier was once one of friendship and collaboration, but it was destroyed by Cain's monstrous actions. Addams acts as both his betrayer and his antagonist, forcing him into his new existence. His relationship with Jennifer Record is defined by his exploitation of her dying daughter, Alice, as a mere test subject, an act of ultimate callousness that highlights his lack of empathy. The entity that was once Alice remains a crucial figure, embodying the consequences of his sins and forming a new bond with his amnesiac self, Ido.

The character's development is one of rejection and separation. For years, the being known as Ido lives without memory of his past as Cain. When Addams finally returns these memories to him, the knowledge is a heavy burden. Ido is confronted with the horrifying truth of who he used to be. However, he does not embrace his past identity. Instead, he actively and firmly rejects it, choosing to remain Ido, the excavator who has formed bonds with a new crew and learned to value something beyond data and research. Through his memories, Ido also gains crucial insight, realizing that the Rajeevs adapt and evolve, making them impossible to permanently defeat through conventional means.

As a scientist, his most notable ability was his unparalleled genius in developing the Mind Trance system, a foundational technology in this universe. This intellect, however, was his primary tool for both creation and destruction. As the amnesiac Ido, his abilities are more practical, including expert piloting of his I-Machine in dangerous excavation and combat scenarios, though this is an evolution of his existence rather than a holdover from his time as Cain.