On the fifth day after becoming a full time hero, Saitama didn't do anything special other than staying in his house. But Genos reveals a terrifying truth to him, that C-Class heros has a certain amount of quota that they need to reach, and a report must be sent every week. Otherwise, they will be dropped from the registry. Upon hearing that, Saitama rushes to the streets to search for cases, but nothing happens. As the deadline gets closer, Saitama gets more frustrated. Suddenly, Speed-o'-Sound Sonic, self-proclaimed Saitama's rival, appeared before him, challenging him for a match, making the situation worse. Can Saitama keep his name in the heroes registry?