I don't know what the source of that synopsis is so I'm going to be working off of the official site and Wikipedia.
The term 先祖返り (senzogaeri) refers to a descendant who manifests traits of distant ancestors. I looked into it a bit more, and the formal term appears to be atavism
. Since atavism refers to the phenomenon and not the person, I assume that makes the person an atavist (yes, it's a real word, I looked it up).
In this series, "Atavist" specifically refers to distant descendants of Demons (youkai
) that mated with humans. An Atavist is someone who suddenly manifests Demon traits, even though for generations their parents have been normal humans.
Clans to whom an Atavist is born are rumored to prosper, and thus Atavists are hailed as the second coming of the clan's Demon ancestor. However, as you might expect, there are many who fear, hate, and seek to kill Atavists, since they hold such strange Demon powers. Our heroine Shirakiin Ririchiyo (CV: Hidaka Rina) is one such Atavist, the descendant of an oni
. Being an Atavist, she's constantly targeted, and so she's looking for a bit of security.
Now that the background is out of the way, on to the introduction from the website:
The high-class apartment complex "Mazon do Ayakashi"[*], also known simply as "The Ayakashi", is said to boast the strongest security around. Rumors abound about it: "The place is full of lunatics," "The place is like a haunted mansion." However, in reality, it is a strange apartment complex where the human descendants of Demons, the Atavists, live!
Troubled by her clumsiness in human relations, Shirakiin Ririchiyo arrives at The Ayakashi in the hopes of rediscovering herself. There she meets her SS (Secret Service), a bodyguard that The Ayakashi provides, one to each resident. His name is Miketsukami Soushi. Soushi entreats Ririchiyo:
"Please, make me your dog!"
* I transliterated it straight from the Japanese, but I think the first two words are meant to represent something in another language; French perhaps. "Mansion du Ayakashi"? I don't know French, I'm afraid.
EDIT: A friend says it's "Maison". Still dunno about the "do" though.