Place it as the closing beat of a chat-screen edit, after the final on-screen reply, and put WhatsApp Message Sound Button just before it so the incoming alert sets up the exit, then let the goodbye close the scene.
關於此聲音
This is a brief spoken goodbye, lasting about one second, delivered in a single casual voice. It feels light and friendly, like waving off a friend at the end of a chat rather than making a formal farewell. The short, direct delivery makes it easy to recognise instantly and use as a simple sign-off in a conversation.