Chapter One

Izuku moved from Bakugou's tormenting to a random neighborhood not to far from Yuuei. There he finds two notebooks, called 'Thunder Breathing' and 'The fight against Muzan'. Next to it was a sheathed sword. What will happen when Izuku learns how to use Thunder Breathing and gets into Yuuei? What will happen once a new demon appears and he is the only one that can kill it?