Yo-kai Watch: Wakuwaku Nyanderful Days (Yo-kai Watch: Exciting Nyanderful Days) is shoujo manga based on the Yo-Kai Watch game series starting with the second game. It is drawn by Chikako Mori and began in December of 2013.
Katie is an eleven year old girl who meets two youkai, Jibanyan and Whisper, at an antique shop. She befriends them and gains a special Yo-kai Watch that allows her to see yokai.
Though the manga has never appeared outside of Japan, strips based on the series are viewable in Yo-kai Watch 2.