The Lost Ones are wanderers who come here from a distant world known as "Japan." No one knows how or why they leave their homes. The only thing that is certain is that they bring disaster and calamity. The duty of exterminating them without remorse falls to Menou, a young Executioner. When she meets Akari, it seems like just another job...until she discovers it's impossible to kill this girl! And when Menou begins to search for a way to defeat this immortality, Akari is more than happy to tag along! So begins a journey that will change Menou forever...

Journey to where the fog never lifts… Libelle, a city by the sea. Those who venture into its fog are said never to make it back alive—a murderous phenomenon that’s another of the Four Major Human Errors that has ravaged the world. But for Menou, it just may be the solution she’s looking for. To fulfill her role as Executioner, she needs to find a way to murder Akari, the girl who seems to spring back to life whenever she’s killed. Maybe this time, Menou will be successful in carrying out her duty... but a calculated encounter with Manon, the daughter of Count Libelle, shifts all their fates in a direction that even Akari never could have predicted. Just what will become of the Executioner and her seemingly unkillable target...?

Pandmonium in the mountains. Hoping to avoid a future where Menou dies trying to save Akari, the girl from Japan runs away with her sworn enemy, Momo. The pair ride the rails to a secluded village in the mountains where they believe they’ll be safe for a few days. Unfortunately, they’re not the only ones who decided to stop off there. Manon and Pandmonium have arrived as well, and they aren’t alone. Akari had hoped keeping away from Menou would be enough to spare the girl she holds dear, but keeping the Executioner alive may require a more drastic course of action...

In the port city of Libelle, where one of the Four Major Human Errors is sealed, Menou and company are tasked with finding the origin of the drug monstrine. They each begin their undercover operations, but nothing goes quite according to plan—Menou is attacked by an unexpected foe, Momo is caught in a trap, and Akari goes missing! And when the time comes to face off against their greatest suspect, Manon Libelle of the Fourth, Menou will learn just how terrifying a Human Error truly is...

To kill Akari, Menou scours the outer reaches of the West in search of a legendary blade that turns all it touches into salt. There, she stumbles across Sahara, a monk, who has history with the young Executioner and begs her to take her life for reasons unknown. Meanwhile, one of the Four Major Human Errors begins to unfold in the undeveloped regions of the East and slowly inches toward them, leaving a trail of destruction in its wake...

MAKE WAY FOR THE POWER OF SCIENCE (AND TENTACLES)! One week after the Undead Festival, the squad's forest fortress gets blown sky-high! In a fit of desperation, Six decides it's time to call in the big guns. Enter Lilith the Black-one of Kisaragi's Supreme Leaders! Her peerless intellect and near-limitless arsenal of deadly weapons are sure to speed up the planetary conquest. This toootally isn't a ploy to get one of Kisaragi's elites to do all the dirty work for a change. If only Alice would get with the program instead of constantly trash-talking Lilith. Seriously, what's with the rebellious phase? Is that any way to treat her creator?!

A BROKEN HERO After learning what Jean did to Flum and witnessing what horrors the spirals have wrought on Maria’s body, Cyril finally snaps. Fleeing the castle, she wanders the streets until she crosses paths with a child named Mute. This chance encounter puts her story on the fast track toward tragedy as the capital counts down to a chaotic anniversary!