Kurumi Tokisaki X Reader

(Y/N)'s a rare kind. A boy with a far deeper history and life than even he realizes. Now living with Shido and the others he attends Raizen High. One day he finds an old friend, neither recognizes the other at first. But what happens when his past comes out, nearly killing one of the people closest to Shido, and putting him apart from them all? Will he salvage what little humanity he has left and try to create light in his dark dominion? Or will he only be redeemed by the love of the last person he expects to find it from.