A gentle story about a girl learning about the world and people.

Due to the job demands of her parents, who repair old buildings and works of art for a living, nine-year-old Mou Yuu has traveled from the city to a rural village. In this village, where the lush greenery of nature has been preserved, Yuu makes new friends and has many adventures with them. Perhaps because of her heritage, or simply because she is in such close contact with nature, she encounters the supernatural and mysteries that cannot be explained.

Zi Bu Yu was serialized in Japan in the Ultra Jump magazine as Daremo Shiranai: Zi Bu Yu (誰も知らない 〜子不語〜) from the March 2009 issue to the August 2010 issue. The Chinese and Japanese versions vary, and the dialogue and narrative have been localized to meet the tastes of their respective markets.

In 2008, Zi Bu Yu was awarded the gold medal in the fifth Golden Dragon Award. In 2009, it was strongly recommended by both Japanese cartoonist Matsui Eimoto (松井荣元) and Shigeki Yukio (茂木行雄), the chief editor of Shueisha.