The daughter of a noble house, Keen spends much of the earlier part of the series trying to prove herself. Her father, choosing to serve Drake to uphold the family name, is killed in combat against Nie's forces (Keen herself has to fight him.) Keen is a loyal, if not exactly skilled fighter, and is able to hold her own well enough until the final battle, even if she sometimes lets her want to prove herself get the better of her. While versed in the use of Aura Battlers, more often than not Keen serves as a support pilot, sortieing in the Fou fighter unit. She has feelings for Nie, but he does not seem to notice them.