When Shoutarou Tatewaki first meets Sakurako Kujou, he knows his life will never be the same. Initially believing her to be responsible for a disappearance in the neighborhood, he later learns of her true talent: analyzing bone specimens. Sakurako has quite the collection of reconstructed animal bones, but she wishes she had more of the human variety, much to the chagrin of those around her. Soon, Shoutarou begins accompanying the eccentric osteologist on the many different unsolved cases she comes across—usually in the form of decomposing bodies. But with so many incidents happening around them, could there be a larger mystery at work in their lives? Sakurako-san no Ashimoto ni wa Shitai ga Umatteiru is a story of two unlikely partners, each showing in their own way that bones can tell how one died, but only people can tell how they lived.

Thanks to the Sibyl System, the mental states of society can now be measured on a numerical scale. Using these crime coefficients, a culprit can be apprehended before they ever commit a crime. But is it a perfect system? For Inspectors Kei Mikhail Ignatov and Arata Shindou, that remains to be seen, as their career with the Public Safety Bureau's Crime Investigation Department has only just begun. Shindou and Ignatov are assigned to investigate the crash of a ship carrying immigrants, but they begin to suspect that it was no mere accident. Meanwhile, a mysterious group called Bifrost is observing them from the shadows, but they are not the only ones who have taken an interest in the two new Inspectors.

Immortality is something many people would wish for. But would it be such a coveted ability if people knew they would be subject to countless attacks because of it? Such is the case for Rin Asougi, an immortal private investigator, because there is no shortage of people who want her dead. Over the centuries, she has met many grisly ends, but each time, she returns to life as if nothing had happened. In 1990, while looking for a lost cat, Rin runs into Kouki Maeno, a man who feels that his memories are wrong. Agreeing to help him, Rin discovers that Kouki is not what he seems, all the while drawing closer to her true enemy. This adversary knows Rin and her kind all too well, and if she dies by his hand, she may stay dead permanently.

In 19th-century France, the wife of vampire noble Jean Duchet Godard is murdered in her own home. With the local human authorities unwilling to properly investigate the case, Godard hires a pair of private detectives known to specialize in the supernatural: Tsugaru Shinuchi, a man with a mysterious birdcage; and his partner, Aya Rindou. This enigmatic duo has come from faraway Japan for one purpose—to track down the man who stole both Aya's body and Tsugaru's humanity.