When Nabu Island's one and only hero retries, someone else starts taking over. Someone just known as the Samurai of Nobu Island. And old myth come to life. Taking care of the truly bad things and training to become something more powerful. Soon enough, UA High sends a class of student heroes and things start to get complicated for the Samurai. On the other hand, a student who graduated from college already and is only sixteen is taking care of the residents another way. Babysitting the Shimano siblings, selling medical supplies you can only get from the mainland and gettign money by selling things to the vacationers from the mainland by selling things you can only get on the mainland at her store. She does everything she can to do the right thing, even if she can't do much. When she meets a hero with good morals, she decides she wants to help him out. He's not running around wasting his energy on small things. He knows that these people won't get anywhere if they can't do simple things on their own. Nobu Island is filled with all sorts of wonders, but they're trapped. What's to happen when the only heroes on the island are children? Villains decide it's a good place to take over.