xxxHolic is a Japanese manga series written and illustrated by the manga group Clamp between 2003 and 2010. A continuation, xxxHolic Rei, was started in 2013.
The series, which crosses over with another Clamp work, Tsubasa: Reservoir Chronicle, revolves around Kimihiro Watanuki, a high school student who is disturbed by his ability to see the supernatural, and Yūko Ichihara, a powerful witch who owns a wish-granting shop. When Watanuki asks Ichihara to remove his ability to see spirits, she grants it on the condition that he pay for his wish by working for her.