Issei Hyoudou, or just Issei was an exorcist that had no memory of his past. He was one of the strongest exorcist of all time, due to possessing many special abilities, however a recent encounter with two Nekoshous changed his thoughts and ideologies, he was starting to see the lies of the church and spared them causing him to be excommunicated. However he did not go down without a fight, he surpassed all expectations and managed to escape but not before leaving a mark on the church, causing him to be considered one of the most dangerous excommunicated stray exorcists in existence. But as fate would have it, things will get even more complicated for our amnesiac protagonist. HighSchool DXD belongs to Ichiei Ishibumi JJK belongs to Gege

In the middle of a possible Stray hunt, Rias Gremory accidentally ended up with three marks on her hand due to activating an unknown spell. After researching them, she discovered their use of calling forth a possible familiar. But what came from the summoning was a familiar that not even a Devil could have ever imagined.