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Succubi, like the young princess Astarotte "Lotte" Ygvar, require the life seed from men to survive, replenish their magic, and continue the royal lineage of the magical realm. This means succubi are required to keep a harem of men close at hand. Ironically, Lotte despises men, which will put her life at risk once she matures. To convince her to fulfill her duties, one of her attendants, Judith Snorrevik, goes to the human realm to find a human male whom Lotte can tolerate. Judith returns with 23-year-old Naoya Touhara, a single father who unfortunately leaves his daughter, Asuha, behind in the human realm. As the first member of Lotte's harem, Naoya quickly adapts to this new environment, serving the princess to make her happy, rather than viewing her with sexual intent. Unfortunately, when his daughter is allowed to arrive in the magical realm, Naoya's relationship quickly worsens with Lotte. Even so, he strives to patch up their relationship. It soon becomes clear, however, that Naoya's presence in the magical realm is more than just mere coincidence. As he develops his bond with Lotte, fate begins to pull together the connections that tie him and everyone else within this enchanting world. [Written by MAL Rewrite]

Azmaria Hendrick gives some background information on characters and the setting, with flashback scenes from the Chrno Crusade series itself. Released with DVD volumes 2-12.

Several generations after the original Yatterman series, Leopard lives with her mother and guardians, Dorothy, Voltkatze, and Elephantus, just outside the prosperous Yatter Kingdom. She lives a happy if impoverished life, unaware of her ancestral ties to the infamous Doronbow Gang, until she discovers a mural of Doronjo, Boyacky, and Tonzura in a sealed off area of her home. It turns out that Dorothy, Voltkatze, and Elephantus are descendants of the villainous gangsters, which is why they have been forbidden from entering the hero Yatterman's Kingdom! At first, Leopard vows to never engage in villainous actions like her ancestors, but new circumstances may mean that she must go back on her word, donning the identity of villain in search of true justice.

Tanis, a child genius, is the youngest son of two mad scientists. His family has spent their lives withdrawn from normal society living on an isolated island, where the couple conducts experiments on Tanis' siblings that result in them gaining abnormal abilities. However, this activity is put to a stop when they are caught and arrested. Tanis is brought by government officials to a more populated island, alongside his four siblings: Snow, a dog-human hybrid; Ashise, a plant-human hybrid; Aisley, a spider-human hybrid; and Suishi, a mind-reader. Being the only one who has not been genetically modified, Tanis takes on the responsibility of adapting his siblings to society, all while trying to conceal their' distinctive characteristics. [Written by MAL Rewrite]