Long ago, a Shinso ("First Ancestor" in English manga) named Alucard tried to wipe out the human world by absorbing countless other monsters to gain the power necessary. Another Shinso and her two comrades fought and defeated Alucard, using her power to seal him away in eternal slumber (which was a grave miscalculation). Because of their exploits, these three later became known as Three Dark Lords.
With the Devil Item, Rosary of Judgement, the Three Dark Lords founded Yōkai Academy and sealed it away from the Human World with the Great Barrier, hoping to continue a peaceful coexistence with humans. One of them, Mikogami, became the Headmaster of the school. The other two Dark Lords, Akasha and Touhou, went their seperate ways and had families.
Upon Akasha's return, she along with Mikogami, Touhou, and Alucard uses a self-destruction spell to end their journey and move on to a new journey leaving behind their dream of humans and monsters coexisting to the next generation. The Three Dark Lords together with Alucard vanished from the world and were never seen again anywhere. No one knows what happened to them after their disappearance.
The Dark Lords are the highest ranking available to a monster, though it is more of a title than rank. They are the most powerful of all the Ayashi in the world. Though their species vary, Akasha Bloodriver being classified as a "Shinso" Vampire and Touhou Fuhai a Yasha, their skills and power are undeniable. No one knows if the title was given or self-imposed the title but three individuals kept that title for fighting and defeating Alucard, giving them a rank above S-Class. Only the strongest of monsters or those with a suicide wish will take on a Dark Lord. Interestingly, Alucard noted Akua Shuzen to be their superior in combat, saying, "In terms of raw skill, not even the Three Great Dark Lords can compare".
- Akasha Bloodriver (Head Of The Dark Lords): Due to the Shinso blood flowing in her veins Akasha has near instantaneous regeneration abilities that allow her to heal throughout all her battles. She is a powerful opponent, one said that when becoming serious that nothing could beat her. Her strengths are equal with her healing abilities allowing her to defeat immortal opponents such as Alucard. As said by Touhou Fuhai, Akasha is titled Nosferatu.
- Mikogami Tenmei: The current Headmaster of Yōkai Academy, he possesses the Rosary of Judgement, a powerful artifact that can create barriers. He possess powerful sealing skills as he was able to seal the Ghoul nature inside Tsukune with a Holy Lock, something that not everyone can do, though the extent to his skills is not known. It is presumed he has more skills than just creating barriers and seals.
- Touhou Fuhai : A yasha who excels at creating and performing seals. He was the one who originally invented the Hougetsu Jigen-Tou and a several other high level seals such as Moka's Rosary and the BakuRyujin, the seal that obliterates dozens of monsters in one hit. He seems to be dying as he reverts to a shriveled form of himself as to conserve "what little life-force he has left.".
- Issa Shuzen: Issa is a Dark Lord in the anime only. In the manga, he is the lover to Gyokuro and Akasha as well as the father to Moka and her sisters, Akua, Kahlua, and Kokoa. His appearances in the manga is when Tsukune, Mizore, and Fuhai Touhou are pulled into Moka's Rosary and later in the Epilogue After Story. Not much is known about his abilities other than his natural Vampiric traits and abilities.
- Given their different personalities and skills, they are a group of different people who united for the common good.
- Only Tenmei appears to have no descendants/offspring which made him declare his successor, with no blood relations to him, who was Tsukune Aono.
- Issa Shuzen is one of the Dark Lords in the anime.