Tobias, Mary, and Sakuya challenge the impregnable "The One Sin", but they lose their way in the maze and unintentionally trap other guild members. A mysterious cat is watching their blunder. Is it another player character or NPC?

In the year 2021, a parasitic virus known as "Gastrea" infects humans and turns them into monsters. What is left of mankind now lives within the Monolith walls, walls that are made of Varanium, the only material that can hurt Gastrea. To counter the threat that the Gastrea pose, "Cursed Children"—female children whose bodies contain trace amounts of the virus which grant them superhuman abilities—officially called Initiators by the Tendo Civil Security, are given partners called Promoters, people who work to guide and protect the young Initiators. These teams of two are sent out on missions to fight the monsters created by the Gastrea virus and keep them at bay. Black Bullet revolves around the team of Enju Aihara, an Initiator, and Satomi Rentaro, a Promoter, as they go on missions to fight the growing threat of Gastrea in their hometown of Tokyo. [Written by MAL Rewrite]

Seishuu Handa is an up-and-coming calligrapher: young, handsome, talented, and unfortunately, a narcissist to boot. When a veteran labels his award-winning piece as "unoriginal," Seishuu quickly loses his cool with severe repercussions. As punishment, and also in order to aid him in self-reflection, Seishuu's father exiles him to the Goto Islands, far from the comfortable Tokyo lifestyle the temperamental artist is used to. Now thrown into a rural setting, Seishuu must attempt to find new inspiration and develop his own unique art style—that is, if boisterous children (headed by the frisky Naru Kotoishi), fujoshi middle schoolers, and energetic old men stop barging into his house! The newest addition to the intimate and quirky Goto community only wants to get some work done, but the islands are far from the peaceful countryside he signed up for. Thanks to his wacky neighbors who are entirely incapable of minding their own business, the arrogant calligrapher learns so much more than he ever hoped to. [Written by MAL Rewrite]

Yu-yu is a boy living in Kanazawa, Kaga Province. He is 15 years old and in his third year of junior high school. He has the ability to sense the feelings of others, but he is troubled by the fact that he cannot say no when asked. One day, Yu-yu could no longer stand going along with his sister's hobby, so he ran away from home. The one who saves him is Megumi Okura. Megumi invites Yu-yu to a nighttime amusement park called "Wonder Hill" where her friends hang out. At the amusement park, Yu-yu meets Megumi, Zakusa Ishikame, and Tomari Seto, members of "Team Blackout," a group that meets to play Vanguard every night. Tonight, a serious fight for the team's flag will take place. Blackout's leader, Danji Momoyama, and the mysterious and powerful fighter, Touya Ebata. As Yu-yu stares at them, the card fight is soon eroded into a world of images. This is how Yu-yu encounters Vanguard, a world he has never seen before, and is drawn in by its powerful allure- making new friends along the way. (Source: ANN)