Realistic setting: In 2026, a "30-day cooling-off period for divorce" was added to the Civil Code. Xu Youran and Jiang An submitted an application on their wedding anniversary, but due to tight housing supply, they had to live under the same roof for 30 days. The two agreed on "roommate rules": use public areas at different times, not bring people of the opposite sex home, and not interfere with each other's lives. Xu Youran starts a blind date, and Jiang An is pursued by a young colleague. Until the 15th day, Xu Youran's mother was suddenly hospitalized, and Jiang An instinctively handled everything as a "son-in-law"; on the 25th day, Jiang An's father brought a remarriage invitation, and Xu Youran subconsciously protected him as a "daughter-in-law." In the last 24 hours, they discovered that the "evidence of cheating" that led to the divorce was actually a misunderstanding created by Jiang An to protect Xu You - he was involved in commercial extortion and pretended to be cheating to force her to leave.