Orphaned when Roland authorities executed his taboo-breaking biological parents after a failed escape attempt, Lach Velariore was spared along with his adoptive brother Moe by Major Rahel Miller. Miller, who had been ordered to eliminate the entire family, falsified their deaths, raised the boys, and employed them as his personnel, cultivating Lach's fierce loyalty.

Lach now serves energetically and impulsively in the Roland Empire's military, part of the Taboo Breaker Pursuit Squad under Captain Milk Callaud. His distinctive orange hair marks his presence. While he sometimes clashes with Milk's direct leadership, he respects her authority and prioritizes squad unity. Lach embraces the unit's core principle of mutual support, viewing them as a "family" that stands by each other's choices.

He operates closely with his brother Moe and squadmates Luke Stokkart and Lear Rinkal. Their team dynamic is defined by absolute trust, forged through shared history and Major Miller's enduring influence.