The pets of Xingluo City are hiding a secret: they may be demon spirits that have cultivated for a hundred years. The socially anxious Su Xiaotang activates the “Demon Spirit Pet Care System” and opens a pet boarding house. Her first problem: the rabbit demon, White Dumpling, sneaks cake and gets a stomachache.
“Don't worry, its spiritual energy is just out of balance.” Shen Zhiyan, a veterinarian in gold-rimmed glasses, arrives with a brew of spirit herbs. A gentle brush of his fingertips steadies the demon energy. From then on, he becomes a regular at the boarding house, always bringing an extra “pet nutritional drink” that is really for the sleep-deprived Su Xiaotang. The System suddenly pops up a message: “Ding! Romance side quest unlocked!”
Their feelings grow as they care for the demon spirits: their fingertips touch while giving medicine, they set up a mosquito-proof barrier while gathering spirit herbs late at night, and they hold hands and dance at a pet competition. Su Xiaotang botches fox demon Lin Yue's flirting lessons, bear demon Dali offers help in his blunt, straightforward way, and White Dumpling pretends to be sick to get the two of them in the same frame. When a chandelier comes crashing down, Shen Zhiyan reveals his antlers in a moment of panic. Only then does Su Xiaotang learn that he is a deer demon who has lived for two hundred years, but she just smiles and says, “I don't mind.”
The “couple's herb-gathering basket” and “comforting wrist warmers” give them a boost, while the System never stops teasing them. Su Xiaotang goes from being socially anxious to daring to give him spirit-herb cookies, and Shen Zhiyan goes from hiding his identity to openly declaring his love. The boarding house becomes a cozy home shared by humans and demons.
In the end, Su Xiaotang's “Demon Spirit Pet Paradise” and Shen Zhiyan's “Spirit Pet Health Center” face each other across the street, with flowering spirit herbs that scatter pink petals planted by their doors. Shen Zhiyan offers her a spirit-herb milk tea. “Want to go see the spirit herbs bloom?” Su Xiaotang smiles down at White Dumpling in her arms. Suddenly, she understands what her grandmother wrote in her diary: true affection knows no boundaries between species, whether for pets or for a beloved.
