uncanny relationship formed by a quirk of fate; a couple strangely but happily united
A yojijukugo describing a relationship (often romantic) that seems to have been brought together by a mysterious, almost miraculous twist of fate. Emphasizes the inexplicable bond between people.
Those two are a couple who seem to have been brought together by a mysterious twist of fate.
As the saying 合縁奇縁 suggests, human relationships are mysterious things.
Rare variant with 相 (mutual).