Imouto

Imouto is the Japanese term for little sister, used for actual blood relatives, or people standing very close to one, and is like a little sister.

In these cases, unless given consent, imouto-san or imouto-chan is the decent phrase, fitted with the necessary honorific, giving respect.

Similar to other Japanese phrases common in today’s English in otaku and weeb circles, imouto got adopted mainly because of the anime and manga influence, starting in the 80’s.

The big brother version of the phrase, onii-chan is also utilized widely.

Thanks to message boards, forums and blogs revolving around anime and manga, the phrase got adopted in plenty of peoples’ dictionaries.

The influence of hentai also helped rooting the term in English, mostly because of the massive amount of incest and lolicon hentai being created.

Urban Dictionary added a definition on imouto in 2009, to enlighten all to-be otakus.

• Honey’s Anime – What Does Imouto Mean?
• Urban Dictionary – Imouto