The Hunter

RWBY x Male Reader x Fate Series x Highschool DxD.
Y/N Kyūketsuki Kirā was a mysterious person. At his time at Beacon, he was the kind of person, who just saw everything as a mission. If he succeeded (which he did all the time) he just went back to training. A girl, with the name Summer Rose, decided to talk to him. At first, Y/N didn't even acknowledged her, but slowly but surely he began to open up to her. After some time, he became friends with Team STRQ and became the boyfriend of Summer. He was happy that he had finally someone to love. But good things can't last forever. When Y/N came back from a difficult mission a little to early, he catched Summer making out with Taiyang. After he saw that, he reverted to his old self. An emotionless killing machine. When he went out for a really difficult mission ALONE, he didn't come back. A search party was send to his last known location and the only thing that they found, was a left arm. They tried to find out who's arm that was and found out that it was indeed, Y/N's arm. Several years later, a strange individual appeared and killed Devils, Angels and Fallen Angels. That individual was actually Y/N, who was summoned by the Holy Grail itself, to kill other Servants, who have gone rogue. He also had the task to kill any Devil, Angel and Fallen Angel who tried anything with Holy Grail and/or the Masters of the summoned Servants. What would happen if Y/N meets a group of girls, who remind him of some old friends? Will the girls succeed in breaking the hunter out of his shell? If so, who will help them? Who knows.
Disclaimer: I don't own aynthing. Just this story.