| In the Heart of Kunoichi Tsubaki | |
 First tankōbon volume cover, featuring (from left to right) Asagao, Tsubaki, and Sazanka | |
| くノ一ツバキの胸の内 (Kunoichi Tsubaki no Mune no Uchi) | |
|---|---|
| Genre | Comedy[1] |
| Manga | |
| Written by | Sōichirō Yamamoto |
| Published by | Shogakukan |
| Imprint | Monthly Shōnen Sunday Comics |
| Magazine | Monthly Shōnen Sunday |
| Demographic | Shōnen |
| Original run | January 12, 2018 – May 12, 2023 |
| Volumes | 9 |
| Anime television series | |
| Directed by | Takudai Kakuchi |
| Written by | Konomi Shugo |
| Music by | Yūsuke Shirato |
| Studio | CloverWorks |
| Licensed by | Crunchyroll |
| Original network | Tokyo MX, GYT, GTV, BS11, MBS, CTV |
| Original run | April 10, 2022 – July 3, 2022 |
| Episodes | 13 |
In the Heart of Kunoichi Tsubaki (Japanese: くノ一ツバキの胸の内, Hepburn: Kunoichi Tsubaki no Mune no Uchi) is a Japanese manga series written and illustrated by Sōichirō Yamamoto. It was serialized in Shogakukan's shōnen manga magazine Monthly Shōnen Sunday from January 2018 to May 2023, with its chapters collected in nine tankōbon volumes. An anime television series adaptation produced by CloverWorks aired from April to July 2022.