Imōto wa Shitteiru

妹は知っている · いもうとわしっている

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Year2025 〜 2026

Volumes7

Latest volumeVol. 7 2026-06-29

Estimated circulation~0.3M est.

DemographicSeinen

StatusOngoing

Publisher講談社

est. Rough estimate based on volume count, reprints and magazine — not an official figure

Overview

At work, Kiichiro Miki is an ordinary salaryman who is considered expressionless and dull by his co-workers. He floats around at drinking parties and doesn't seem to be having any fun at all. But only I, his younger sister, knows the truth about him. My brother is actually “the most interesting man in the world." (Source: Kodansha, translated)

Source: AniList

Synopsis 日本語

職場では無表情でつまらないと思われているサラリーマン三木貴一郎。その彼の正体は実は伝説のハガキ職人だが彼の面白さを知っているのは妹三木美貴だけだった。そんな同居する兄と妹で色々やり取りする。

Source: Wikipedia「妹は知っている」 (CC BY-SA 4.0)

雁木万里Author

Gag Comedy Comedy Slice of Life

External databases: Wikidata · AniList

How to compare editions, collected volumes and ISBNs / Sources, updates and corrections

Volumes

ヤンマガKC First edition 7vols · 2025-03〜2026-06

#	Release	ISBN	Buy	Price	Pages
Vol. 1	2025-03-12	9784065387887	Rakuten · Amazon PR	720 JPY	174
Vol. 2	2025-06-23	9784065399484	Rakuten · Amazon PR	720 JPY	171
Vol. 3	2025-08-01	9784065405376	Rakuten · Amazon PR	720 JPY	172
Vol. 4	2025-10-27	9784065411384	Rakuten · Amazon PR	720 JPY	172
Vol. 5	2025-12-29	9784065417638	Rakuten · Amazon PR	720 JPY	172
Vol. 6	2026-03-23	9784065428832	Rakuten · Amazon PR	720 JPY	172
Vol. 7	2026-06-29	9784065438282	Rakuten · Amazon PR	720 JPY	172