Shirogane Takeru is a typical high school student with a lazy attitude and a love for the virtual reality mecha battle game Valgern-on. His life takes an unexpected turn when he finds a girl he doesn't remember ever meeting in his bed one morning. She immediately moves to his house and starts changing his life for the good.

Former magic student Kurou knows little of grimoires, but what he does know terrifies him--enough that he left his university life behind, and now practices a failing detective business. But just when he thought his Academy past was buried, it catches up with him and pulls him back into the dark shadows of the occult.

Azai Kyousuke, the son of a legendary gangster, spends his time playing God at school and covertly working for his stepfather. This idyllic existence is broken when two individuals appear in the city--a beautiful girl named Haru and an international gangster known as 'Maou'. The two begin a deadly cat-and-mouse game.

A group of friends have customized their microwave into a device that can send text messages to the past. As they perform experiments, an organization doing their own research on time travel tracks them down. The characters must now find a way to avoid being captured by them.

Wilfred pursues a dream of becoming an alchemist. However, soon after gaining his license he gets entangled with three girls with differing personalities and goals, and he soon agrees to hire them as his guards in order to help each other out.