Magical Girl F***ing Marathon

From the introduction: In the year 2015 the Organization for the Preservation of Human Order, Finis Chaldea, was destroyed. A traitor had placed a bomb inside their control room, killing 46 of the 48 master candidates, the director, and countless staff. Since then, Chaldea has been limping along, slowly fixing the eight singularities created by the traitor and his master in the wake of the attack.