We still don't know the rules of that star. Kenji (Hayato Isomura)'s catchphrase when he's feeling down is "MUMUSU." This adorable keychain features a bold design incorporating a distinctive line from the work. ☆ The two star motifs express Kenji's personality as a lover of astronomy, and it will comfort your "MUMUSU" feelings when you're a little tired or worried... Size: Approximately 60mm It's currently sold out at the Kantel Store.