Imouto

[Little_Girl]

Imouto (ee-mo-oo-toh) is the Japanese Romaji for little sister.

When referring to ones own family, or someone who is not unlike family, such as a lifelong or childhood friend, it can just be said as imouto. However, when referring to another family, you should always add a suffix on the end, such as imouto-san, unless given consent otherwise.