**Twelve years apart, reunited by fate.**
Cheng Nuan never imagined she would run into Zhou Hanyang, the childhood friend who left without a word twelve years ago, right across the hall from her own home. The boy who had shared her entire childhood was now an accomplished director at a tech company: mature and steady, yet still mindful of all her little habits.
**“Cheng Xiaonuan, long time no see.”**
His simple greeting tore open memories long buried. Their sudden separation, the letters returned unopened, the promises left unspoken: all had become thorns in Cheng Nuan's heart. She had planned to keep her distance, but fate entwined their lives once more. He became the technical lead on her company's project, and she became someone he could not ignore.
**“I’ve seen every building you’ve designed.”**
It turned out he had never truly left. He had kept her university portfolio, followed her career, and even saved the wishes she had mentioned in passing. But just as Cheng Nuan finally gathered the courage to draw closer, her former boss began making things difficult, Zhou Hanyang's ex-girlfriend appeared, and office politics drove their relationship to a freezing standstill.
**“If red means stop and green means go, what does yellow mean?”**
**“Wait.”**
**“I’ve waited for you for twelve years, Cheng Nuan.”**
When the truth comes out and the misunderstandings are cleared away, Zhou Hanyang uses a promise they made as children to light a signal lamp for her on a rainy night. A year later, on the playground of the elementary school where they first met, he kneels on one knee and brings to life the “dream proposal” she once drew in her diary.
