Kean Keats hails from a noble Byston Well lineage. Her father, upholding the family honor, swears allegiance to Drake Luft. This loyalty compels him into battle against Nie Given's resistance forces. During a clash, Kean confronts him directly in combat, resulting in his death.

Following this pivotal loss, Kean joins Nie Given's faction. Loyal and determined, her combat prowess falls short compared to other aura battler pilots, relegating her primarily to a support role piloting the Fou fighter. Her eagerness to prove her worth sometimes triggers impulsive choices in the field.

Kean harbors unreciprocated romantic feelings for Nie Given. This emotional attachment endures despite his lack of acknowledgment and his entanglement with Riml Luft, daughter of their adversary Drake Luft. Kean remains an active combatant against Luft's forces, fighting through the conflict's final battles.