xxxHOLiC (×××ホリック, Horikku), pronounced "holic", is a seinen manga series planned and presented by Clamp. The storyline of xxxHOLiC crosses over with that of a number of other CLAMP series, the most notable of which are Tsubasa RESERVoir CHRoNiCLE which was written in tandem with it, and Cardcaptor Sakura whose history it draws on at several points. xxxHOLiC is also connected with the series Blood-C though not shown in xxxHOLiC due to the time difference.