The Karma Fate Destiny That Brings Lovers Together in Chinese / Japanese...

姻緣 means “Destiny that brings lovers together.” It can also be translated technically as “Predestined matrimonial affinity” (wow, talk about taking the romance out of this word - that was from the Oxford C-E dictionary).

This speaks to the fate (or karma) that brings a husband and wife together. I would translate this as “Together by fate” or “Joined by destiny” but in the context of marriage. You could use this for non-married lovers, but the first character has a suggestion that this refers to those that are married.

This literally translates as “the red string” or “the red thread” in Japanese, but the real meaning is much deeper...

In Japanese culture, it's believed that fate, destiny, or karma joins lovers by an unseen string, tied around one little finger of each. 赤い糸 is how soul mates find and are drawn to each other.

The Japanese concept of the red thread of fate, by most estimations, comes from Chinese folklore, where it's known as 姻緣紅線. The only difference is that in China, the celestial red thread is tied around the ankles of the lovers (versus what is usually represented as the pinky finger in Japan).