While exploring the National Library, Miaka Yuuki and Yui Hongo are whisked away into a fantastical realm by a peculiar book emitting a crimson light. In this new world, they face perilous slave traders but are saved by Tamahome, a formidable young man marked with a Chinese symbol on his brow. However, their joy is short-lived as Yui is abruptly snatched away by the same crimson glow. Determined to rescue her friend, Miaka seeks Tamahome's aid. Matters complicate when they cross paths with Hotohori, the empire's ruler, who identifies Miaka as the legendary priestess destined to awaken the god Suzaku by uniting with his seven Celestial Warriors. Eager to fulfill her wishes, Miaka agrees to the task, a proposition that aligns with Hotohori's ambitions to safeguard his nation. Meanwhile, back in the real world, Yui watches on helplessly as Miaka embarks on a perilous journey as the heroine of the mystical book.