Kimihiro Watanuki is haunted by visions of ghosts and spirits. He seeks help from a mysterious woman named Yuko, who claims she can help. However, Watanuki must work for Yuko in order to pay for her aid. Soon Watanuki finds himself employed in Yuko’s shop where he sees things and meets customers that are stranger than anything he could have ever imagined.
 
(Source: Kodansha USA)
 
Notes: 
- The series was re-named to xxxHolic&bull;Rou on chapter title pages of chapter 186 and on, but not on their volume's front covers, spines and indicia. 
- The chapter count contains a one-shot published in May 2010 to commemorate the switch, which was later collected into Volume 18. 
- The chapter count also reflects the magazine releases; the chapters plus the one-shot were re-arranged into 109 chapters across 19 volumes.