The first-generation hunter Cha Eunha, who had gone missing inside the mysterious and secretive Unknown Gate, is back. Clad in a jet-black dress and carrying a parasol, she had no choice but to stay inside the gate to save her comrades. After surviving by taking down monsters, a human unexpectedly appears before her. And finally—Eunha returns to the real world. "Welcome to the world 30 years later, senior." What unfolds before Eunha... is a world 30 years in the future.