Saina, known as Saiga in Japanese and other dubs, is a pilot in the Hakkeshu, an elite mecha unit serving the Hau Dragon organization. He operates the elemental-themed mecha Bryst Of The Fire. Genetically engineered by scientist Masaki Kihara alongside his fellow Hakkeshu pilots, Saina possesses deliberately implanted psychological flaws. His personality manifests extreme aggression, volatile behavior, and cruelty, making him the group's most unstable member and contrasting sharply with the level-headed pilot of the same mecha unit. These engineered "jerkass" tendencies fuel interpersonal conflict, contributing to Rockfell's romantic rejection of the dependable Giso in Saina's favor.

During Hau Dragon's missions targeting the stolen Zeorymer and its pilot, Masato Akitsu, Saina engages in combat. This culminates in a final assault where the remaining Hakkeshu mechas, including Bryst Of The Fire, attack simultaneously. This triggers the emergence of Masaki Kihara's dominant personality within Masato. Masaki/Kihara reveals to the pilots that they are all clones derived from his zygote, burdened with specific, exploitable neuroses. Dismissing their defiance and inherent flaws, Masaki/Kihara activates Zeorymer's ultimate weapon, "Meiou," annihilating the attacking mechas and killing Saina along with the other pilots.