He is her brother and she is his sister. She said she was the sunset, and he said she was the most beautiful sunset in his heart. He developed an abnormal affection for her and reluctantly went to study in a foreign country; her dependence on him did not diminish, so she traveled thousands of miles just to find him. When she found him, he was very happy. He thought this was God's arrangement and they would live peacefully. However, the intervention of two people disrupted his life again. When he decided to love her regardless of everything, he was told that she was getting married. What action will he take? What did she do to derail everything? What color will the dusk after sunset be?