You've got the uniquely-Japanese part right.
In the Great Japanese Novel "The Tale of Genji" (written in the Middle Ages, and thus arguably the first novel ever wriiten anywhere in the World), the eponymous hero, Prince Genji, is always struggling the juggle a lifetime rotation of mistresses (and their intense jealousies of each other), always having 3 at any given time.
The mistresses always picture their rivals as "the spitting image" of other women in Genji's life.
I realize it's just an idiom, but I've always found the word choice to be significant.