A passing comet with mysterious powers brings about wonderful human relationships. A dog owner and a cat owner start to exhibit animalistic traits whenever they're unhappy, yet their unusual ordeal enables them to discover the true meaning of happiness. When Comet WTF666 chose the earth as its target and its pinkish tail swept around the world, it meant to spread happiness and love to humanity. Miao Yu is a tacky CEO with an entrepreneurial mind. Wang Chen is an introverted designer who doesn't mix well within fashion circles. Their fates become intertwined because of a livestream and an accident at the pet hospital. From then on, once they feel unhappy, Miao Yu starts acting like Wang Chen's cat while Wang Chen starts acting like Miao Yu's dog. It's an arrangement that brings occasional surprises and occasional distresses.

One is the a hardworking and cold boss, the other is a talkative and strong female soldier. These two people who seem to be from two separate worlds, but come together by mistake. They start their well-matched love story.

Chen Chuyun, a quiet and well-behaved young woman, has only ever done one rebellious thing: becoming an online artist. One evening, her peaceful life is disrupted when a woman named Liu Qian appears in her home, claiming to be from a distant planet and warning her of a mistake in her compatibility with Han Zi'ang. Unconvinced, Chen dismisses her claims, but Liu Qian is determined to fix the issue in her own way.

Du Xinyue, a poor girl facing family upheaval during troubled times, bravely manages her family's tavern while searching for the truth behind her father's mysterious death. Alongside her love interest, Su Xingluo, she uncovers the real culprit and works to protect their home and the people.