A virus spreads across the world, transforming all humankind into wild, slavering, furry beasts: cats, to be precise. Those few survivors who remain human take refuge in the dark corners of the earth as they fight back against the feline horde. Kunagi, a man with no memory of his past yet a deep knowledge of cats, struggles to hold on with only his wits and a will to survive. Yet the virus transmits merely through cuddles, and Kunagi finds kitties so hard to resist! Is his willpower strong enough to withstand this hair-raising cat-tastrophe?

In the detective business, everyone knows the name Keiichirou Nagumo. Back in high school, he was called a genius for cracking tough cases that even the police could not solve. But those days are long gone—or so the rumors say. However, one day, an unexpected visitor barges into his office: Mashiro, an energetic high school student who demands to be hired as his new assistant. Although Keiichirou tries to brush her off, Mashiro is persistent. She is determined to become a detective, and to prove her worth, she begins by teaching him about the latest technology and offers a fresh perspective on his business. Thus, Keiichirou takes Mashiro on as his assistant and embarks on a brand new chapter in his career—one where he finds himself constantly surprised by the modern generation of detectives.

Mogura, a mysterious "self-proclaimed sage" also known as Hyakuan Momoyumi, has been banned from the afterlife. To return, he roams the world, collecting the "lamps" of ghosts in his lantern. However, crossing paths with him brings an unusual consequence: the ability to see strange phenomena...

Despite being one of the most promising candidates, Allen fails the final exam for the position of royal court sorcerer, forcing him to abandon his ambitions and return home. Adding to his woes, he does not even have enough money for the train fare back, stranding him. With help from a former professor, Allen secures an unusual job offer: to be the private tutor of the daughter of Duke Howard, one of the kingdom's most powerful nobles. The girl, Tina, however, has one critical flaw—she is completely unable to use magic. Though her academic prowess is nothing short of prodigious, intellect alone is not enough for the fast-approaching entrance exams to the prestigious Royal Academy. Moreover, countless magic instructors have tried to solve her problem and gave up in the process. To help Tina overcome her limitations, Allen must dig deeper into the roots of her magical inability, and, in doing so, uncover far more than he ever signed up for.