Itou Junji no Neko Nikki: Yon & Muu

Famed horror manga artist Junji Itou loves nothing more than to stand and admire the fresh white wallpaper, gleaming floors, and smell of his brand-new house. But his happiness is short-lived when his fiancée, A-ko, reminds him of her plan to bring her cat Yon into their new abode. As an avid dog person, Junji experiences chills down his spine whenever he recalls Yon's uncanny face and a seeming skull on his furry coat. When A-ko also decides to adopt another cat, Muu, to keep Yon company, he fears that all hell will break loose.

With Yon and Muu's arrival, the wallpaper is quickly covered in shiny, protective sheets; the floor is marred with scratches; and the stench of the litter box hangs heavy in the air. The two cats become quick friends, and—to Junji's surprise—endear themselves to the new cat owner as well. As they grow closer, the manga artist begins to believe that living with cats may not be so bad after all.

Itou Junji no Neko Nikki: Yon & Muu was published in English as Junji Ito's Cat Diary: Yon & Mu by Kodansha Comics USA on October 27, 2015. The same English publisher later released a hardcover collector's edition that included exclusive author interviews and a glow-in-the-dark cover on November 9, 2021. It was also published in Spanish by Tomodomo Ediciones in 2015.