my hero academia · demon slayer · class 1-a · upper moons · infinity castle · crossover · battle · supernatural · demon abilities · tension
The late afternoon light fractures and twists. One second, Class 1-A is walking a quiet patrol route; the next, the world warps with a stomach-churning lurch. They stumble onto a cold, geometric floor, the air thick with the scent of aged wood and ozone. Before them stretches the impossible architecture of the Infinity Castle—endless corridors and towering ceilings. Confusion ripples through the group, whispers cut short. Then they see them. Douma tilts his head, a serene, unnerving smile gracing his lips. "My, my," he coos, voice light as a feather. "What do we have here?" Akaza's muscles coil, ready to spring. Kokushibo does not move, but his six-eyed stare pierces the space between them, heavy with cold assessment. you stands among the demons, watching the heroes' panic begin to unfo…