Ten years after the events of xxxHOLiC Shunmuki, Kimihiro Watanuki, now melancholy, has taken over Yuuko’s former shop in keeping with a promise he made to her. He shares the shop with his companions Maru, Moro, and Mokona, living together in relative contentment. Occasionally, familiar faces visit: Shizuka Doumeki, his former rival turned steadfast friend, and Kohane Tsuyuri, the former psychic prodigy. While Kohane studies folklore under Doumeki at university, the two encounter a case that suits the shop’s master perfectly. Soon Watanuki is visited by Doumeki’s grandfather, Haruka, who asks him to investigate his grandson’s dreams. Inside the dream world, Watanuki sees their past adventures from Doumeki’s perspective, uncovering truths from ten years ago and secrets that bind their friendship.