Kara no Kyoukai is a series of stories written by Kinoko Nasu with illustrations by Takashi Takeuchi.
The first five chapters were posted online on Nasu and Takeuchi’s dojin website “Takebouki” starting Oct 1998, and the last two chapters being released at Comiket 56 in 1999. In 2001, part of the story was included in “Tsukihime PLUS-DISK,” created by TYPE-MOON, the doujin circle Nasu and Takeuchi joined. The story gained huge popularity, and the doujinshi edition of the stories saw release on December 30, 2001 at Comiket 61.
Note; The cover image is from The Garden of Sinners non-novel volume 1 edition published in 2004.