There Is A Demon Deep In The Mountains

Pei Shaoyu, a young man from the prestigious Pei family of Jiangxia, flees after his parents are murdered and his family is destroyed. Hunted by the Pei family and other martial arts sects, he is severely injured and poisoned with nearly a hundred types of toxins. Exhausted and near death, he collapses in a dark forest and is discovered by Zhu Ying, a reclusive woman living in a remote mountain hut. Zhu Ying, who claims to be a former disciple of Medicine Valley, initially intends to use his corpse to test her new medicines. However, she is surprised when he survives her attempts and decides to treat him instead, using a brutal method of fighting poison with poison through medicinal baths.

During his month-long recovery, Pei Shaoyu endures excruciating pain but gradually heals. His extraordinary blood, which possesses potent healing properties, is revealed to be the key to his survival and also becomes significant when Zhu Ying suffers from a monthly condition that causes her meridians to break and repair repeatedly. Pei Shaoyu discovers that his blood can alleviate her pain, establishing a complex bond between them. Zhu Ying provides him with a sword manual and teaches him martial arts, helping him regain his strength. Meanwhile, the Pei family, led by the vengeful patriarch Pei Wang, continues to search for him, determined to avenge his brother Pei Shaoan, who was crippled by Pei Shaoyu.

As Pei Shaoyu recovers, he learns that Zhu Ying is far more powerful than she lets on, displaying martial arts skills that surpass those of the guest elders sent by the Five Great Families. When the Pei family tracks them to the mountain, Zhu Ying effortlessly eliminates the attackers, including renowned guest elders from other sects. The conflict escalates as Pei Wang allies with the Jin and Jiang families, sending more warriors to capture Pei Shaoyu alive. Zhu Ying kills the attackers in a rain-soaked night, but the constant threats force them to consider leaving their secluded home.

Zhu Ying reveals that her condition requires rare treasures from the Four Major Sects to cure. Pei Shaoyu, driven by gratitude and a desire to repay her, bets that he can obtain these items within two years. In exchange, Zhu Ying agrees to accompany him down the mountain. The story shifts from their isolated mountain life to the broader martial world as they prepare to face the combined forces of the Five Great Families and the Four Major Sects. Pei Shaoyu must balance his quest for revenge against his growing connection with Zhu Ying, while she remains an enigmatic figure with her own hidden past and motives.

The narrative explores themes of survival, loyalty, and the blurred lines between healer and poisoner. Zhu Ying's true identity and origins remain mysterious, hinting at a deeper history in the martial arts world. Pei Shaoyu's journey transforms from one of mere escape to a deliberate confrontation with his enemies, fueled by his determination to protect Zhu Ying and uncover the truth behind his family's destruction. As they descend the mountain, they face increasing danger from powerful factions seeking to exploit Pei Shaoyu's unique blood and Zhu Ying's formidable skills.