Putting his life on the line, Willem Kmetsch leaves his loved ones behind and sets out to battle a mysterious monster, and even though he is victorious, he is rendered frozen in ice. It is during his icy slumber that terrifying creatures known as "Beasts" emerge on the Earth's surface and threaten humanity's existence. Willem awakens 500 years later, only to find himself the sole survivor of his race as mankind is wiped out. Together with the other surviving races, Willem takes refuge on the floating islands in the sky, living in fear of the Beasts below. He lives a life of loneliness and only does odd jobs to get by. One day, he is tasked with being a weapon storehouse caretaker. Thinking nothing of it, Willem accepts, but he soon realizes that these weapons are actually a group of young Leprechauns. Though they bear every resemblance to humans, they have no regard for their own lives, identifying themselves as mere weapons of war. Among them is Chtholly Nota Seniorious, who is more than willing to sacrifice herself if it means defeating the Beasts and ensuring peace. Willem becomes something of a father figure for the young Leprechauns, watching over them fondly and supporting them in any way he can. He, who once fought so bravely on the frontlines, can now only hope that the ones being sent to battle return safely from the monsters that destroyed his kind. [Written by MAL Rewrite]

Several years ago, local heroines—superhero characters who represent towns and perform stage shows in order to raise their town's acclaim—had a boom in popularity. The most famous of these local heroines, Kamidaio, is scheduled to perform in the small town of Hinano, much to the excitement of Mikan Kise's little sister Yuzu. Unfortunately, when Mikan takes Yuzu to the show, she finds out that it has been canceled. She promises her distraught sister that she'll make sure she can see the show. Desperate not to let her down, Mikan asks her classmate, the local heroine fanatic An Akagi, for help. Mikan and Ann put on their own Kamidaio performance clad in homemade costumes, which the kids in the audience love despite its lack of production value. The show is recorded by the student council president Misaki Shirogane, who posts it online to garner attention. Misaki is from a family of politicians and has taken it upon herself to revitalize Hinano. Impressed by their show, she recruits Mikan and An to become the official local heroines of their town. As the group works to improve their shows, they enlist the help of a variety of colorful individuals. [Written by MAL Rewrite]

Haruka Shinozaki has been interested in the class representative, Akiho Kousaka, since his first year in high school. She is attractive, good at sports, and is an all-around model student. Since they are in the same class this year, Shinozaki decides to confess his feelings—and, to his shock, Kousaka agrees to be his girlfriend! However, he finds that Kousaka is a bit stranger than he first thought: this seemingly perfect girl has never been in a relationship. But even though she is inexperienced, she vows to please Shinozaki in every way she can... such as learning multiple sex positions or his fetishes. Shinozaki tries to assure her that her studies into such subjects aren't necessary, but Kousaka devotes herself to making him happy in more ways than one. [Written by MAL Rewrite]

As the united world fights for its freedom against the alien forces known as the Neuroi, human girls with magical abilities—called witches—continue to battle. With the persisting conflict affecting morale, Grace Maitland Steward, a retired witch who still serves in the army, presents a plan advocating the power of music as an invaluable support that can change the tides of war. Unfortunately, her proposal is written off, prompting Grace to find a way to prove the potential of her idea to her superiors. She enlists the help of Aila Paivikki Linnamaa and Eleonore Giovanna Gassion—two witches who have already seen some success as singers—to recruit other witches and form the League of Nations Air Force's Music Squadron. The campaign manages to produce seven promising candidates. Among them, 14-year-old Virginia Robertson, despite having no military experience whatsoever, seems to possess an ability too significant to ignore. [Written by MAL Rewrite]