Krest Saber Hargen is a pilot and a core member of the Sonic Diver team, which supplies vital air support to the AEGIS organization. He initially presents himself as a brash and arrogant pilot who delights in displaying his skill and will regularly disregard orders in favor of high-risk, self-assured maneuvers. Beneath that exterior, he holds a genuine care for his teammates and is prepared to place himself in danger to protect them. The central tragedy of his past is the loss of his younger sister during an enemy attack, a loss that fuels a powerful drive for revenge against the opposing organization and heavily shapes his motivations throughout the story. As the narrative progresses, his arrogance is tempered by experience; he grows more reflective and his bonds with his comrades deepen, revealing a more layered personality beneath the initial bravado. In combat, he is a highly capable pilot, adapting quickly to changing circumstances and relying on sharp reflexes and focused analytical judgment during defensive operations and high-risk aerial engagements. His role places him at the heart of AEGIS's defensive efforts, making him a pivotal presence in the ongoing conflict.