A person who is as small as dust and has never known what self-confidence is. He feels like a rock sinking to the bottom of the sea, unable to struggle and never able to surface.
The other is a man who looks like a radiant sun but is trapped in the water. He clearly knows that his life is only in the deep seabed, so he indulges himself in it and swims down the river.
They meet in unknown ocean currents and embrace the sun on the horizon.