Oyakodon♥: Oppai Tokumori Bonyuu Tsuyudaku de

In February 1999, a string of murders has Shiki Ryougi and Mikiya Kokutou on edge. These crimes share a disturbing resemblance to a similar set of homicides from 1995, when Shiki and Mikiya first met, and awaken a dark, murderous desire that has laid dormant within Shiki's soul ever since then.

As the Overfiend slumbers, the mad emperor Caesar rises to power, enslaving a new race of demon beasts. Into this cruel existence is born the Lord of Chaos, the Overfiend's nemesis. As the blood-thirsty beasts capture the tyrant's daughter in a brutal coup, the Overfiend must awaken to an apocalyptic battle of the Gods.

Legend has it that the human race is not the only dominant civilization living on Earth. Two other races exist in this world: the Makai (a demon race) and the Jujinkai (a half-man, half-beast race). Once every 3,000 years, a supreme being known as the Choujin (Overfiend) will emerge and bring balance to all three realms on Earth. In present-day Japan, after 300 years of endless searching, a Jujinkai named Amano Jyaku has discovered the presence of the Choujin inside high school slacker Tatsuo Nagumo. But now, Amano, along with his sister Megumi and their sidekick Kuroko, must protect Nagumo and his new girlfriend Akemi Ito from the Makai, who believe that Nagumo is not the Choujin, but an evil entity bent on destroying all living beings on Earth.

When ancient dark magic falls into sinister hands and unleashes ages of suffering onto mankind, a group of heroes from different eras and cultures must band together in order to defeat it at all costs.

July 1998 - After a group of delinquents is found dead in their hangout place with all their limbs twisted and torn off, Aozaki Touko receives a request to find the murderer and asks Shiki for help. The main suspect is Asagami Fujino; a girl who was the boys' plaything until recently, who Shiki believes to be "one of her kind".

A peace treaty between the Earth and the Black World, a parallel universe of demons, is coming to an end. Two cops, Taki, a human male, and Maki, a female demon, are assigned to protect a diplomat who will help secure another treaty. A radical group of demons from the Black World are out to assassinate the diplomat and prevent the treaty; only the bond that forms between the two cops can save the Earth from destruction.