Syaoran, Sakura, Fay, and Kurogane barely escape with their lives and make it to the country of Nihon, where Kurogane is originally from. There, they place the unconscious Sakura in the boughs of the giant sakura tree in the courtyard while the others rest and recuperate from their recent experiences. Things change when Seishirou arrives from another dimension as Syaoran challenges him to a fight for the feather he stole. Their fight leads Syaoran to the dream realm where he discovers Sakura's soul as well as Watanuki from 
xxxHOLiC. However, Syaoran-clone arrives and a whole new fight is about to begin as well as shocking revelations.
[2 OVA/OAD episodes based on a story from the manga of the same title by CLAMP. This OAD crosses over with xxxHOLiC Shunmuki.]
Also see prequels -
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