While recovering from surgery, Minekura Kazuya is asked by the Zero-Sum editor-in-chief Koyagi to create a series of illustrations for the manga magazine Zero-Sum Ward. To create a theme, Koyagi rolls four dice: two hold character names, one holds a situation, and the last holds an action. With each roll, characters are placed in strange situations, much to Minekura's chagrin.
The Last Saiyuki summary: Returning from school, third-grader Ryunosuke is introduced to a young girl. His father tells him that she will be his little sister starting that day. Her name is Koharu. She is blind and her arms and legs are prosthetics. She holds within her a power beyond human understanding... A bizarre and fantastic Saiyuki story for a new generation!
From MangaUpdates: The boys of Saiyuki are at it again! As they continue their journey west, they come across a mysterious village, isolated from the outside...the only human residence still standing in a mountain full of youkai. No matter where these boys go, trouble always follows!