Kim and Rain grew up in a family that demands them to take over the family business. Rain, the older brother, is expected to be an heir by his father while Kim is always being compared to his older brother. Every time Kim is hard-pressed, he always retreats to his safe zone which is in the water and his garden. At the same time, it’s Sun’s birthday, but there’s only an automatic message that wishes him happy birthday. Therefore, even though he lives in a big and crowded city, Sun feels lonely in his room.