"Yatogame-chan Observation Diary") is a Japanese four-panel manga series written and illustrated by Masaki Andō.

High school student Tohiska Jin moves from Tokyo to Nagoya where he learns through his new schoolmate Monaka Yatogame and her friends about the peculiarities of life in his new hometown and the quirks of its inhabitants.

[1] Satsuki Hayasaka is the character designer, and WORDS in STEREO is credited for series composition.

[31] The season, titled Yatogame-chan Kansatsu Nikki 2 Satsume (八十亀ちゃんかんさつにっき 2さつめ), premiered from January 5 to March 22, 2020, with the cast and staff reprising their roles.

[34] The season, titled Yatogame-chan Kansatsu Nikki 3 Satsume (八十亀ちゃんかんさつにっき 3さつめ), aired from January 10 to March 28, 2021, with the cast and staff reprising once again their roles.

The season, titled Yatogame-chan Kansatsu Nikki 4 Satsume (八十亀ちゃんかんさつにっき 4さつめ), is produced by Hayabusa Film, with Creators in Pack credited with animation cooperation.