The Anatomy Lesson of Dr. Nicolaes Tulp

JoJo's Bizarre Adventure: The Anatomy Lesson of Dr. Nicolaes Tulp (『ジョジョの奇妙な冒険 テュルプ博士の解剖学講義』) is an unreleased light novel written by in 2000. The story took place in Morioh a year after the events of the fourth part of JoJo's Bizarre Adventure, Diamond is Unbreakable. It featured several new original characters drawn by Hirohiko Araki.

An incomplete 30-page rough draft was released in a December 2002 issue of Yomu Jump (a special novel-based issue of Weekly Shonen Jump) along with a full release date in February 2003, but the novel ended up proving difficult to complete. In the annual Japanese guidebook, Kono Mystery ga Sugoi 2004, Otsuichi claimed to have written over 2000 pages, but had thrown them all out. Intent on writing a novel that lived up to the manga, it took him until 2007 to complete it. The finished novel ended up being a completely different story and titled The Book: JoJo's Bizarre Adventure 4th Another Day.

Summary
The story centers around a nine-year old boy named Kaoru and his mother. The two of them move into Morioh a year after the events of Part 4. The apartment they moved into was previously owned by and, a couple that Yoshikage Kira killed. A robbery case from three years ago resurfaces, and Kaoru's mother is frightened by a mysterious stalker. Kaoru befriends Josuke Higashikata and learns various things about Stands and the history of the town. Kaoru encounters an old man in the park who ominously asks if his mother is hiding anything. He is eventually taken away by a nurse.