+ David
- Protagonist: A Mecha boy programmed to love, symbolizing the potential and limitations of AI.
- Motivations: To become a real boy and earn Monica's unconditional love.
- Development Arc: Remains static in his core programming, highlighting the deterministic nature of his existence. His 'growth' is learning the cruelty of the world.
- Relationships: Obsessively attached to Monica, forms a complex bond with Gigolo Joe, seeks guidance from Professor Hobby.
+ Gigolo Joe
- Secondary Character: A pleasure Mecha on the run, representing societal exploitation and the search for meaning.
- Motivations: Survival and finding a place in a world that rejects him.
- Development Arc: Develops a sense of loyalty and companionship with David.
- Relationships: Acts as David's protector and guide, offering a cynical perspective on love and humanity.
+ Monica Swinton
- Supporting Character: David's adoptive mother, representing the complexities of human love and attachment.
- Motivations: Initially driven by grief over her son's illness, later conflicted by David's programmed affection.
- Development Arc: Struggles with her feelings for David, ultimately unable to fully accept him as her son.
- Relationships: Her relationship with David is the central emotional conflict of the film.
+ Professor Hobby
- Supporting Character: David's creator, representing the ethical dilemmas of artificial intelligence.
- Motivations: To create the perfect artificial child, driven by a desire to understand human love.
- Development Arc: Remains detached and philosophical, observing the consequences of his creation.
- Relationships: His relationship with David is distant and detached, highlighting the creator's responsibility.