Yūri Katsuki carried all of Japan's hopes on his shoulders to win at the Gran Prix Finale ice skating competition, but suffered a crushing defeat. He returns home to Kyushu and half feels like he wants to retire, and half feels like he wants to continue ice skating. Suddenly the five-time consecutive world championship ice skater Victor Nikiforov appears before him with Yuri Plisetsky, a young Russian figure skater who is already defeating his seniors. Victor and both Yuris take up the challenge on an unprecedented Gran Prix series.

In 2012, the world allegedly comes to an end at the hands of a human-made virus, ravaging the global populace and leaving only children untouched. It is at this time that vampires emerge from the recesses of the earth, likely followed by age-old horrors of the dark thought only to be myth. The vampires sweep the earth and claim it in a single violent stroke, subjugating the remnants of humanity and leading them beneath the surface to safety. This "protection" comes at the price of donating blood to their captors. At the age of twelve, Yūichirō and his friend and fellow orphan Mikaela plotted to escape along with the children in Hyakuya Orphanage. However, this resulted in their deaths and Mikaela sacrifices himself in order for Yūichirō to escape and be saved by members of the Moon Demon Company, an extermination unit of the Japanese Imperial Demon Army. Four years later, Yūichirō dedicates his life to destroy vampires and seek revenge against them for murdering his "family".

Kamijo is a student in Academy City, where people use science to develop supernatural abilities. The guy’s got a lot of heart – luckily for a young nun named Index. She’s on the run from a sorcery society that covets the astonishing 103,000 volumes of magical knowledge stored in her memory. When Index stumbles into Kamijo’s life, she find a faithful friend and protector, and while Kamijo’s easily the weakest kid in Academy City, he’s got something else going for him: the Imagine Breaker, an unexplainable power stored in his right hand that negates the powers of others. With scientists and sorcerers attacking from all sides, the Imagine Breaker will definitely come in handy – but it’s Kamijo’s loyalty to Index that will be his greatest weapon in the fight to keep her safe.

Kagami Junichirou was known as a physics genius when he was a teenager, and he was even published in "Nature." However, after college, he suddenly lost all interest in science. As a NEET, he's devoted himself to his anime blog and nerdy collecting habits. He claims he has a serious illness called "I can't do anything I don't want to do." Desperate to get him to do something with his life, his little sister manages to get him a job teaching physics at his old high school. He's certainly an unconventional teacher, but he becomes fairly popular with the students. After helping a girl who's being ruthlessly bullied, Kagami finds that he actually likes teaching. Will he continue his career as a weird teacher? Will he go back into physics? Or will he end up back where he started?

In the near future, spirits and monsters are in full sight. A boy leads a group of people with special abilities as they plot against a massive organization that takes advantage of a certain incident and eventually know the truth about their world in the process.