The Masked King (仮面の王 Kamen no Ou) is a mysterious individual who was the founder of the Miao Family and the organisation Fairy Tale. It's later on revealed that the Masked King is in truth one of the two persona created by Alucard's clone with the other being Miyabi Fujisaki.
Befitting his name, the Masked King hides his true identity with a mask that has five eyes. He wears a round hat and a long cloak. The Masked King also carries a walking stick, which resembles a spinal column and brain.
He wants nothing more than total world domination, going as far as to keep the Huang and Miao families fighting each other and even planning to kill the heir to the Miao Family working for him to control China. Truly a heartless monster, as well as a remorseless lunatic, he will murder anyone who disappoints or betrays him, such as the case with Xia-Long's father. He even made it clear in a chat that if Gyokuro Shuzen were to fail, she too would pay a steep price for failure. He is said by Xia-Long Miao to absolutely hate Touhou Fuhai.
The Masked King is first introduced in a flashback by Xia-Long Miao who remembered when they first met and his sequent servitude under the Masked King's threats after the Masked King showed him his deceased father stuffed into a briefcase. After the assassination attempt on Xia-Long, Routier, Fang-Fang Huang, and Yukari Sendo by the hands of his servant, Gairen Yuki, he discussed with Gyokuro Shuzen about how killing Xia-Long after he served his purpose allowed the Masked King to control all of China. During the conservation the Masked King made it clear that if she failed him then she'll meet the same fate.
After Gyokuro's death by the hands of Moka reclaiming the Rosary that the older vampire took to control Alucard, the Masked King appeared and attacked Touhou Fuhai from behind and thanking Tsukune Aono for all the events that led up till then.
It is revealed in Chapter 65 that the Masked King is actually Miyabi Fujisaki, leader of the 1st Subdivision of Fairy Tale. However, Touhou Fuhai recognises him from his past and proclaims that "Miyabi" is a fake name; the man is actually Alucard. Alucard laughs, telling Fuhai that his present form is a clone created before his body was sealed away by Akasha 200 years ago. Thus, Alucard assumed the persona of the Masked King and created the Miao Family and Fairy Tale, while working as "Miyabi Fujisaki" under Gyokuro Shuzen to assess whether Moka Akashiya's Rosario had the ability to control Alucard's main body.