In the last thirty days of his senior year in high school, Wen Qiao was transferred by his class teacher to work next to Lu Xu. She was a poor student at the bottom of her grade, drawing cats in class and folding papers into paper airplanes; he was a top student in his grade, his mother was laid off and his father worked night shifts for rent, so his only way to get into college was to do well in college. On the first day he changed seats, he moved the paper half an inch toward him, and the gap between the two desks became a boundary between Chu and Han. But the orange candy still rolled over - the candy she placed on the gap, he put it away in the drawer. The evening breeze on the rooftop, the crooked stars on the draft paper, and the unintelligible songs in the headphones pushed people from two worlds through the gap. Fourteen days before the college entrance examination, he confessed his love on the rooftop. But they knew from the beginning that he was going to a distant place and she was going to stay where she was. Score evaluation, application filling, admission, the reality gap silently tears apart all tacit understandings. On the rooftop, he said "Take care" and "You too". He went to a prestigious school thousands of miles away, while she stayed locally. The orange candy wrapper was torn in half, half in the wallet and half on the pillow. What they lost was not the distance, but their lives that were destined to be at odds with each other from the moment they met. No one did anything wrong, it was just inappropriate. This is the tenderest regret in youth.