Trinity Seven, Trinity Seven: 7-nin no Mahoutsukai, Trinity Seven: Shichinin no Mahoutsukai

"One day, the bright red sun stopped shining, causing the 'Breakdown Phenomenon'—the destruction of Arata Kasuga's city and the disappearance of the people who inhabited it. However, all was not lost; by utilizing a magical grimoire given to him by his childhood friend and cousin, Hijiri Kasuga, Arata's world was artificially reconstructed."