Kara no Kyoukai: The Garden of Sinners
Kara no Kyoukai: The Garden of Sinners Manga Summary
From Manga Updates:
A very popular early work from Kinoko Nasu from the Tsukihime & Fate fame, the Kara no Kyoukai universe has meet great success as an animated film adaptation, novels and radio dramas.
Kara no Kyoukai depicts a world were the true dark nature of the human being is being reviewed and exposed by shocking and ruthless events, and in the center of it all we have Ryougi Shiki, the true heir to the long lived, wealthy and mysterious Ryougi clan and Kokuto Mikiya, a would be normal high school student if it wouldn't be for his amazing deductive & investigative progress.
The moment Kokuto and Shiki meet is the moment that the wheel of fate started to turn, however is this fate moving forward naturally of it's own accord, or is it all being orchestrated from behind the scenes by an enigmatic persona? Only time will tell.