General discussion for the novel series Kara no Kyoukai. Spoilers abound.
Kara no Kyoukai (空の境界, Kara no Kyoukai?) is one of TYPE-MOON's earliest works authored by Nasu Kinoko and illustrated by Takeuchi Takashi. It is also known under the name Rakkyo (らっきょ, Rakkyo?), and its tagline the Garden of sinners.
More Info: Type-Moon Wiki
Translation Project: Baka-Tsuki