Marriage is a sacred palace, the home of love, the interpretation of happiness, and the safe haven of the heart... +... However, not everyone who loves each other can enter the palace of marriage, and not every couple who enters marriage does so because they love each other! What can be used to bind love? What can be used to block emotions? In life without rehearsal, accidents will always happen. The male and female protagonists in the novel all have happy marriages, and they never thought of "cheating" in their plans, but God likes to joke and uses the worst way in the world to arrange for them to meet again and again at the wrong time. When an indescribable emotion secretly grows in the darkness, the love on the third floor underground brings them the ultimate joy, and it also brings them the ultimate pain. At the moment when passion merges, they are destined to endure the contradictions, entanglements, and struggles between marriage and extramarital affairs...+...+When love is passionate, crazy, and painful, how will they deal with this unexpected "extramarital affair" that is spurned by others? Perhaps, there is a kind of emotion that is only suitable for fermenting in the dark, exuding a faint and ulterior fragrance...+...