Ao no Exorcist to Kuro no Kenshi

With the Black Swordsman appearing in the world of exorcists and demons under mysterious circumstances after a decisive battle, some events might not go as they were supposed to. Perhaps becoming an exorcist himself and collaborating with a certain black-haired nephilim and his friends will help him get back to his world... SAO and Ao no Exorcist crossover. Mixed anime/manga canon