Robert Altman begins as a military captain in the Cenacle Island Defense Force (CDF), tasked with maintaining island security. Following a major reorganization, he transitions to lead the newly formed Cenacle Island Police Department (CPD) as its chief inspector.

A Caucasian male of middle-to-upper-class heritage, Altman stands 188 cm tall and weighs 103 kg. He possesses a fully organic body, devoid of cybernetic enhancements. He is recognized for exceptional martial arts skill, specifically in "Jyuu-Jitsu," enabling him to confront opponents with advanced cybernetics or weaponry through technique alone.

Personality-wise, Altman exhibits a consistently kind and gentlemanly demeanor driven by a strong sense of justice. He feels inherently compelled to assist those in distress, often explaining his actions with the phrase "it's in my nature." His distinctive, hearty laughter ("HA HA HA") is a recognizable trait. He commands significant respect from subordinates and prioritizes the welfare of Cenacle Island's citizens above institutional or political interests.

Key narrative involvements see him leverage evidence of governmental corruption, provided by Uzal Delilah, to establish the CPD and authorize a raid on a U.S. Imperial facility. During this raid, he collaborates with Nene Nanakorobi and Clarion, who operate under pseudonyms; despite this, Altman deduces their true identities based on contextual clues and their distinctive capabilities. This collaboration results in the arrest of Ian Kurtz and the neutralization of his enforcer, Fear.

Altman's personal life intersects with television reporter Proserpina, leading to a relationship. This connection later results in him being targeted and severely injured by Kerykeion, a figure seeking vengeance against Proserpina. His survival hinges on emergency medical intervention by Keith Brooklyn. Subsequent story developments focus on his recovery and intensified martial arts training.