Over time it slowly enhances the bearer's physical capacities, increasing their combat abilities and intelligence. The bearer is marked with a flower that glows when the power is activate.
As a side effect, the blood of the person becomes alluring to all Vampires, making them sometimes hard to resist the temptation to drink their blood as their blood smells tasty to them. Both Fan Le Lao and Ge Chen end up entranced by its powers at one point or another after one bite. Another power granted is the ability to retain their humanity in spite of being bitten by vampires numerous times and never become a Vampire.
After he takes her as a prisoner, Set mentions that Yue Jian at least only knows how to use the ability as a power up. It has another purpose she has yet to discover. The Sabbat also learns of its actual purpose, while the reveal of the information is hidden for now from the reader of the manhua, Zhao Yan is shown to be deeply upset by the information to the point she cries.
Since they can't be turned into Vampires, they can drink the blood of Vampires to make themselves more powerful. Yue Jian was originally against the idea and firmly rejected it, but after Isis threathened her with her sisters she gave in. The effects yet to be seen.
Eventually also Xi Yan bites her sister Zhao Yan, however Zhao Yan refers to the blood as "dirty" and is reluctant to give her some but had no choice at the time. Xi Yan describes the blood as sweeter then normal blood with a cleansing sensation and a feeling of warmth. The blood merges with the body, becoming one. All while the Vampire's instincts become stronger and the craving making it hard to not stop drinking.
Xi Yan's fake SerumEdit
Although it appeared as a glowing flower like the original and even managed to produce the same scent, it did not grant her special powers or immunity against vampires nor enriched the quality of her blood to allure vampires. In the end, she ends up becoming a Vampire when Yi Sai bites her.
- The concept of Mei Yue Yin is very similar to how hunters become Imbued in Hunter: The Reckoning.
- "Mei Yue Yin" means "Fascination" in chinese.
- Both the girls who received the real dosage have the flower on their left side of their chest, for Xi Yan, her flower appeared on the right. The flower remains on the girls with the real dosage but so far appears missing on Xi Yan. Though it was never stated that the flower had to be on a particular side, it was a subtle hint that Xi Yan's dosage was fake when looking back on the early chapters.
|The Demon Hunters|
|Leaders||Hue Ge Lin ● Li Tao ● Yi Shen ● Osiris ● Ada|
|misc. characters||Xi Yan ● Zhao Yan ● Ling Xue Xiao ● Lin Xuan Chi ● Professor Nan Gong ● Kai Lin ● Xue Jiao|
|other||Forbidden Sphere ● Devil Key ● Mei Yue Yin ● Sui Xi Bing Lin|