In a clash against four dominant species—angels, demons, undeads, and beast‑humans—humanity survived only because its hero Sid vanquished each rival champion and locked their legions inside four towering pyramids, and hope for tomorrow. Decades later, when Sid is remembered merely as a myth, Kai Sakura Vento serves soldiers assigned to guard those pyramids, wary that the ancient enemies might once again break free. Night falls, wind whispers old tales.
One tranquil afternoon while he spent time with his comrade Jeanne E. Anise, the world abruptly "rewrote" itself, sending Kai into a parallel realm where demons had nearly wiped out humanity and forced the survivors to hide. Distant drums echo unseen foes' march. To worsen matters, Kai"s very presence vanished from that reality; every ally—including Jeanne, now the leader of a local resistance—had forgotten him.
Seeking clues to his vanished home, Kai meets Rinne, a mysterious young woman imprisoned within a pyramid. Rinne's eyes mirror sorrow, and her resolve fuels their quest. By some strange twist he inherits Sid"s famed blade, the Codeholder, and frees Rinne from her confinement. Determined to restore balance, Kai allies with Rinne and Jeanne to liberate humanity from demonic domination. Yet for the brave warrior to return to his own world, he must first discover why reality was so dramatically altered. Every step toward pyramids feels risky.
