Sora Mukushima lived a modest but peaceful life with his parents—until everything changed. One day, a mysterious tower appeared, his soldier brother went missing, and monstrous creatures began attacking without warning. In the face of death, a strange man from Sora’s dreams appeared, pulling him into another world: a dark, unforgiving realm known as “The Abyss.” Now stranded in this hostile dimension, Sora must fight to survive, grow stronger, and find a way back home. Driven by the desire to save his family and uncover the truth behind the Abyss, he steps into a battle that will test his limits—and his very humanity. At the edge of despair, destiny awaits.