Ten people from the "Mirror World", a parallel universe originated from Earth's various branch of fate, sacrificed themselves to defeat an ultimate evil that invaded their world. These 10 people were collectively known as "Legendary Heroes” finished their duties and peacefully died after leaving the Mirror World in the care of three rulers. However, A few years after those heroes died, people from earth started getting pulled through mirrors by the monsters of the Mirror World so that they might feed.  To counter this, the three rulers made a decision, one would sacrifice himself to give power to Earthling, one would use Phone Application to guide Earthling while the other one would protect the Mirror World Meanwhile, Arisato Tsubasa was your ordinary high schooler, still learning about his newly found power until he soon discovered that fantastical monsters existed. There were some people who didn't deserve to be saved. That he must sometimes fight in order to stop the fighting. At the same time, he must also cook his dinner, did the laundry and studied for the test.   Disclaimer Not a native English speaker Write in phones Shitty English ahead