In a world where reality blurs and glitches, two students, Reika and Youko, find themselves lost in an immense, infinite building that challenges all known logic. Their guide through this enigmatic labyrinth is a cryptic message left by Tagami, a renowned game designer, hinting at deeper truths. As they navigate this perplexing environment, unraveling its mysteries becomes crucial not just for their survival but for the fate of humanity itself, casting them as unexpected saviors in a realm shaped by unknown forces.