Manga by author Kawamura Taku

This is a cute story about two elementary school students - the assertive airhead transfer student Takada, and the gloomy girl who's a target of bullies, Nishimura.

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Side stories for My Clueless First Friend (Jijyou wo Shiranai Tenkousei ga Guigui Kuru) posted on the author's Twitter and Pixiv.