S.O.S. is a hero academy manga that takes place in a low fantasy version of Shibuya, Japan. The story follows 12 students of Class 1A as a massive explosion causes a chain of events that change the city forever. As things get more complicated, the characters not only have to face an invisible enemy, they also have to face a much more viscous foe: Themselves.

In this world there is an ability known as "channeling", the capacity to manipulate certain objects at will. Isaac, Milo and Rex, three young veterans from the recently finished War of The Archangels, rent a room in the pawnshop of a certain Serena, located in the suburban district of Kennel City. They hope to move on from conflicts from their past and start a new life, regardless of how hard this might be.

In a fantasy world, Rocky, a human boy, lives peacefully with us aunt, a powerful Witch, on an island where there are only monsters. But one day this island is invaded by a group of Heroes in search of a magical artifact that will change the fate of the entire world.