Imagine your OTP getting married, and having the most romantic first dance song. At the end of their first dance they are both crying silent tears.
Fast forward, they live a happy, married life, fixing their problems, raising a couple of kids. Then at their 60th anniversary imagine all their kids and grandkids (and hey maybe even great grandkids) trying to find that wedding song, all being very disappointed when they can’t.
The whole family goes back to the main dance floor where your OTP is dancing slowly, softly singing their song in perfect harmony.