The Carnival Moment is a time when several narratives from Type-Moon's famous works intersect. It happens every decade in an entirely new dimension, and those who have never run into each other can meet. And what's more, all individuals involved gain the opportunity to fulfill any of their wishes! However, they will have to come a long way, as they will need to partake in contests. In Carnival Phantasm, various characters are put into situations that ridicule their own worlds. Nevertheless, they all have the same objective: to win the contests by any means necessary!

Nen: the hidden source of energy and potential that runs through everyone, and gives those that master it a source of great power. Inside Nen is the potential for limitless light and limitless darkness. The Hunter Association has arisen to control access to it. Hunters come in many shapes and forms, and with many different appetites - but all of them have learned to master Nen, and use it to chase wealth, power, and their dreams. The greatest and most powerful Hunter is Isaac Netero, chairman of the Hunter Association. Decades ago he sealed away Jed, a Hunter who had mastered the use of On, the dark shadow of Nen. Now On users have reappeared at the Heaven's Arena Battle Olympia tournament. For Netero, this is the last mission: to protect the Association and the world from a threat driven by hatred and the thirst for revenge. And he's going to need all the help he can get in order to succeed.

Frustrating, insufficient, and irritating is how most citizens would describe civil servants. However, three new employees are about to discover what really happens behind the scenes. Lucy Yamagami, bent on revenge against the civil servant who allowed her comically long name to be put on her birth certificate; Yutaka Hasebe, an easygoing guy always on the lookout for a place to slack off; and Saya Miyoshi, a nervous first-time worker, are about to experience the underwhelming satisfaction of being government employees. They are supposed to be trained by Taishi Ichimiya, but he has no idea how to do so, even though he has worked there for eight years. With an incompetent senior colleague and unfavorable confrontations with clients, the trio starts to lose faith in their chosen occupation but encourage each other to do their best.

One day, Kei Kusanagi notices a strange glowing woman by the lake. He discovers that the woman is actually an alien officer from the Galaxy Federation named Mizuho Kazami, and even more shocking—she's also his teacher! In spite of this setback, he and his teacher gradually get to know each other and a romance blossoms between them. However, soon enough, the principal of the school finds out about their relationship. The solution? Get married! Together, the newlyweds must keep their marriage a secret, not only from Kei's high school friends, but also the Galaxy Federation. Onegai☆Teacher is the fragile but comedic love story of an alien and her student.