College student Laura encounters Gamura, a subordinate of the Demon King Gante. When she discovers Gamura attacking men, she confronts her but gets overpowered and has her blood drained. Suddenly, lightning strikes, transporting Laura to a mysterious dimension where she receives the sacred power "Soleil" and resolves to fight Gamura again. Meanwhile, the enraged Demon King Gante, furious at being thwarted, plots to steal Soleil's power by creating a powerful bomb and sends Gamura after Laura once more. This time, Laura is caught off guard and drained of her blood again. Taken to Gante's lair, Laura attempts to resist using Soleil's power—but she is about to face an ordeal far worse than she could have imagined.