Place it at the very end of an edit, after dialogue and action have finished, so it closes the scene rather than competing with it. Start with a brief reflective moment, then let this clip carry the farewell, followed only by a short closing sound if you need a final beat.
關於此聲音
This 16-second clip is a soft piano melody with a music-box quality, played without lyrics and fading gently at the end. It feels calm and bittersweet, like quiet comfort mixed with a little sadness at the close of a day. Oyasumi means good night in Japanese, and the tune comes from the indie role-playing game Omori, where it suits the game's dreamlike, emotional mood.