The duet speaks from the infinite but tragic love involving Chang'e and Houyi, who're according to the Chinese fantasy in the moon goddess, upon which the movie is based on. Amongst quite a few artists who've recorded variations of "Always and Forever" is the American R&B vocal group Whistle, who https://alwaysandforever17388.blogdon.net/always-and-forever-mine-for-dummies-53164821