Li Huangxuan, a working-class young man in Jiangcheng, welcomes a short-term roommate named Lin Ximeng. From their first meeting, an inexplicable sense of familiarity arises. Lin Ximeng knows his preferences well and quietly acts as a loyal reader of his web novels. After living together under the same roof for just a month, Lin Ximeng suddenly leaves. When an old illness flares up, Li Huangxuan recovers his memory: three years ago, during a mountain climbing rockfall accident, his lover Lin Ximeng died saving him. She made a wish upon a shooting star, trading for thirty days of time at the cost of completely dissipating when the time expires. On the night of the meteor shower, Lin Ximeng confesses the truth and vanishes into starlight. A year later, Li Huangxuan writes down their story and waits faithfully as promised. Lin Ximeng returns stepping on starlight, and the two commit to each other for life, rewriting a romantic romance that transcends life and death.