Bakugan Interspace is a virtual reality system, where players can brawl against each other and take part in tournaments. Initially designed to help practice and enhance Bakugan skills, it quickly became a meeting place for many enthusiasts. During one of Danma Kuusou's duels, the Interspace crashes, and he gets knocked out cold. Before regaining consciousness, he experiences a vision of Bakugan at war with each other once again. The explosion of energy that accompanied Danma's fight and caused the shutdown of the system sends shock waves across the galaxy, attracting the attention of the Twelve Orders, a Gundalian organization. They infiltrate Bakugan Interspace, looking for strong brawlers to join them in their upcoming war with another alien race, the Neathians. Danma and his companions—Shun Kazami and Chouji Marukura—soon find themselves caught up in an extraterrestrial war. However, distant as it may seem, the conflict threatens the very sovereignty of Earth and the future of the Bakugan race as well.

While exploring a labyrinth, Rentt Faina, an adventurer with lots of experience but little to show for it, is killed by a dragon upon discovering its lair. Shockingly, he wakes up to find himself turned into a skeleton, the lowest class of undead monsters. As Rentt fights against the other monsters of the labyrinth, he discovers that slaying them gains him experience towards higher stages of undead evolution—even ones with flesh! With this revelation in hand, Rentt obtains a new objective in his undeath: keep evolving in the hope of eventually becoming a vampire, the highest form of undead that is nearly indistinguishable from human beings. Despite being forced to hide his past identity and monstrous nature under an unremovable mask, Rentt manages to return to a semblance of his former life. Granted shelter by Lorraine Vivier, an elite researcher and retired adventurer, Rentt assumes her surname and starts over from scratch as a rookie. Determined to pursue his childhood dream and become a mithril-class adventurer, Rentt must be cautious not to disclose his new bodily circumstances, lest the adventurers’ guild seek to exterminate the monster he has become.

Fate Graphite lives miserably as a gatekeeper in a world where skills given at birth determine an individual's entire life. Afflicted by the seemingly harmful skill Gluttony, which makes him perpetually hungry, he is abused by the holy knights—the supposed protectors of the populace—who view him as a dreg on society due to his skill. However, Fate's destiny takes a dramatic turn after he kills an escaping injured thief. To his surprise, Gluttony activates, enhancing his stats and granting him new skills. Following this epiphanic event, Fate receives a job offer from Roxy Hart, the only benevolent holy knight in the city, which he happily accepts. Eager to further explore Gluttony's true potential, he partners with a mysterious talking sword named Greed, who warns him that Gluttony is a taboo skill that breaks the logic of the world. Now forced to live a double life, Fate must slay monsters at night to satisfy his awakened appetite for souls, lest he go berserk and lose all chances at finding happiness.

Takashi Natsume has grown accustomed to his encounters with youkai through the Book of Friends, which contains the names of youkai whom his grandmother, Reiko Natsume, has sealed in contracts. These encounters allow Natsume to better understand the youkai, Reiko, and himself. The Book of Friends is a powerful tool that can be used to control youkai; it is sought after by both youkai and exorcists alike. Natsume just wants to live out his daily life in peace but is constantly disrupted by these experiences. If he is to end this torment, Natsume must explore more about the book and the world of exorcism, as well as begin to open his heart to those who can help him.