Ami wants to decorate a Christmas tree with Amu, so after school, Amu and the Guardians shop for decorations. As the group leaves the store, Yoru steals Su's decoration and Su is separated from the rest of the group. Amu, Ran, and Miki search for Su, but eventually call it a night. Meanwhile, Su befriends a white shaggy puppy who is also lost. The next day, Amu and the Guardians search for Su. Su ...