Synopsis: Sweet Rein

While strolling down the street, 17-year-old Sagara Kurumi collides with a guy, causing mysterious reins to appear and bind them together. To her bewilderment, the boy, Kaito, takes her hands and proclaims her his superior. The situation grows even more bizarre when Kaito transforms into a reindeer, causing Kurumi to faint. As she comes to, it dawns on her that she might be a Santa and Kaito her trusty steed, tasked with a vital mission on Christmas Eve. Additionally, the volume includes one-shots like "Amai Kamiato," "Eden no Tobira," and the "Penguin Kakumei Side Story."