On Christmas Eve, Nichijou’s author Keiichi Arawi Tweeted a sketch which revealed that Yuko, Mio, Mia and Nano were up to no good and trying to catch Santa.
https://twitter.com/himaraya/status/679971083638841344/photo/
On Christmas Eve, he revealed they caught something but it wasn’t Santa.
https://twitter.com/himaraya/status/680417033394098176/photo/1
Source: Keiichi Arawi