The Azure Sword, Slayer of Distortions

Existing among humans are supernatural objects called vanits that encapsulate distortions of the world. Shin Karamori wields one such artifact—an azure sword that granted his wish to live and gave him incredible combat abilities, yet is also fated to destroy him. Karamori spends his days taking on bizarre and bloody cases involving vanits, fighting alongside an artificial girl named Archive whose destiny is decided by a certain book. Archive's body belongs to a figure from Karamori's past who once lifted him out of a pit of despair, and he'll do anything to save her—even if that means Archive disappears. When the tragic pair meet a high school girl, the wheels of fate rapidly start to spin. But is the future awaiting them one of annihilation...or something else?