Amidst the bustling and capricious streets of a vibrant city, two strangers, Rachel and Ethan, engage in a passionate one-night affair. It offers them no illusions of permanence, merely a brief respite from their ordinary lives. The undeniable chemistry between them ignites a momentary blaze of desire in the obscurity of the night. Yet, as the first light of dawn breaks and they reluctantly part ways, the memory of their electric connection lingers, refusing to be forgotten. It becomes evident that destiny has its own plans. Several months later, by a twist of fate, Rachel and Ethan's paths intersect once more, thrusting them into a whirlwind of emotions they never saw coming. Concealing their secrets and carrying the scars of their pasts, they discover an inexplicable attraction drawing them together.

Class A has a couple of top students, while Class F has a couple of underachievers. One weekend, they all stayed overnight at a guesthouse. The underachiever entered the wrong room, and the top student ended up sleeping with the wrong person. From that moment on, the gears of destiny reversed, and their close relationships became disarrayed... The male lead is the top student, and the female lead is the underachiever.

In the mysterious Underworld, at the peak of Purgatory Mountain, Jun Jiao is a powerful figure who commands malevolent spirits. But trouble brews as the energy she relies on starts fading, and a dark plan forms among the spirits. Jun Jiao decides to face this danger and goes into the abyss, where she suddenly loses consciousness. Now, her journey begins to bring balance back and uncover the hidden truths of the Underworld.