Losing their war against Heaven's angel army, the demons of Hell are on the cusp of collapse. As a last ditch attempt to turn the tides of the war, the demons send Akutsu Masatora to the mortal plane on Earth to save their homeland from the angels. Disguising himself as a high school student, Akutsu seeks to recruit someone with the capability to lead the demons to victory. Akutsu does not have to look far: among his classmates is the magnificent Lily Amane, a transfer student who seems like the perfect candidate for Akutsu's plans. But as luck would have it, Lily is one of the very angels that Akutsu is meant to be fighting against, and his attempt to recruit her might end up being the biggest blunder in the failing war. Worse yet, Akutsu may fall in love with his own worst enemy.

Four members of the Din Republic's spy team Lamplight embark on a mission to capture an enemy spy. Although they struggle to work together due to their clashing personalities, Thea, Monika, Erna, and Annett complete their objective. While enjoying a short break, the four girls encounter a woman named Matilda, who claims to be Annett's mother. As they get to know Matilda, the team is dragged into an escalating conflict that tests their teamwork and allegiances. Meanwhile, the remaining Lamplight members notice that the dispatched squad has yet to report back. Worried about their allies, Klaus and Lily set out on an emergency expedition to locate their missing teammates. As the two uncover troubling information about rising tensions in the area where their friends last were, they must act quickly to reassemble the team before the mission reaches the point of no return.

The Armed Detective Agency is still on the run from the Hunting Dogs, but not all hope is lost. Detective Ranpo Edogawa has a plan to prove the Agency's innocence and save the world from chaos: to find and capture Kamui—the leader of the terrorist organization Decay of the Angel. In order to determine Kamui's whereabouts, Ranpo and his colleague Atsushi Nakajima must convince Ouchi Fukuchi, the renowned captain of the Hunting Dogs, for amnesty. Although Fukuchi was tasked with arresting the members of the Agency, his past with the Agency's president, Yukichi Fukuzawa, may be the key to earning his trust. But unbeknownst to them, Fukuchi might not be as honorable as he proclaims.

Despite having accomplished a lifelong dream of hers, Ann Halford faces further challenges ahead. Bridget Paige, the daughter of the Paige Workshop's owner, still possesses the wing of Shall Fen Shall, Ann's former fairy companion. In determination to save Shall from the obsessive Bridget, Ann decides to join the Paige Workshop, hoping at the same time to perhaps reunite with her close friend. Having been appointed head of the workshop, Ann becomes entrusted with rebuilding it to its former glory. She quickly discovers that the Paige Workshop has a unique focus on tradition and individuality, and recognizes that she will need to learn about her team and completely revamp the workshop in order to succeed. Motivated by her strong desire to rescue Shall and her obligations as a sugar artisan, Ann wholeheartedly dedicates herself to her new position.