Volume 9, the latest installment of the hugely popular manga *My Little Sister Knows* by Mari Kanki—currently serialized in *Weekly Young Magazine* (Kodansha)—will go on sale on October 6, 2026.

Mari Kagi’s “My Little Sister Knows” Latest Volume 9 Synopsis

The synopsis for Volume 9 of “My Little Sister Knows” has not yet been announced.
*As of August 19, 2026

When is the release date for Volume 9, the latest volume of Mari Kagi’s “My Little Sister Knows”?

Total sales have surpassed 900,000 copies! The latest volume (Vol. 9) of Mari Kari’s addictive sibling comedy *My Little Sister Knows It All* will be released on October 6, 2026!

Mari Kanki, “My Little Sister Knows”: Synopsis (Recap) of the Previous Volume, Volume 8

Synopsis of the Previous Volume (Details on the Previous Volume, Vol. 8)

Boy-meets-girl stories happen all over the place.

A legendary postcard artist brother and his idol sister.
The brother tries an arranged marriage for the first time, while his sister, Miki, runs into her postcard artist friend, Momi Tiger.
Even her coworker, Hirose, has her first…?

Volume 8 of this sibling comedy where everyone’s encounters intertwine.

Introduction to Mari Kanki’s “My Little Sister Knows”

My older brother is the legendary postcard artist, Fruit Parfait.

At work, he’s seen as a bland, expressionless office worker: Kiichiro Miki.
Even at drinking parties, he stands out like a fish out of water and never seems to be having any fun.
But I, his little sister, am the only one who knows the truth: that he’s actually “the funniest and kindest person in the world”—.

Volume 1 of this heartwarming sibling comedy that gently touches the heart.

Mari Kanki’s “My Little Sister Knows” Latest Volume 9 to Be Released on October 6, 2026!

“My Little Sister Knows” Manga Product Information

Please check the official website for details.
*Please note that the information in these articles may be out of date. We ask that you kindly check the official website for the latest details.

© Mari Kanki/Kodansha