Keith Aero-Windermere

Alienated from his family and peers at a young age, Keith found solace in his friendship with Royd Brem. They both came under the tutelage of Herman Klaus and trained to become part of the Aerial Knights. They were excellent swordsmen and would occasionally spar. Deeply shaken by the destruction of a village in Windermere by the Dimension Eater—a weapon of mass destruction deployed by the New United Nations in the Spaceworld—they vowed revenge after their people's surrender.

As he grew older, Keith came to consider himself the guardian of his ailing half-brother, Heinz. His devotion remained unwavering, even when King Gramia VI used the revived Protoculture ship, the Sigur Valens, to further his plans for galactic conquest. As the war progressed, he developed a bitter rivalry with Messer Ihlefeld. After his father, King Gramia VI, presumed dead aboard the Sigur Valens, Heinz was crowned king; the first Windsinger in over one hundred and fifty years, he tasked Royd with leading the war effort.

Heinz, already weakened from the last battle, is forced to sing the "Song of the Wind" again at Roid's command, causing over half of Al-Shahal's population to fall into a coma. Keith, already horrified by the signs of Heinz's body crystallization, is further enraged to learn that Roid has assassinated King Gramia VI. He decides to defect after witnessing the destruction of Lauri Marine's entire NUNS fleet by its own spatial weapon en route to Windermere IV, as well as his plans to use the "Bio-Neural Network Fold" to bring the entire galaxy to its knees. During the final battle on Ragna, Keith joins Delta Flight and Walküre against Roid's forces. When Freya Wion sings "Ichido Dake no Koi Nara," breaking the spell cast by Roid and Mikumo's song, everyone turns against Roid Brem.

Keith dies along with Royd, piercing him with a sword, but before death, their runes touch, and for a split second the two former