Fifty years ago, horrific creatures dubbed as the "enemies of humanity" suddenly appeared around the world. To combat these threats, teenagers gifted with supernatural abilities called "Talents"—such as pyrokinesis and time travel—hone their powers at an academy on a secluded island. Nanao Nakajima, however, is quite different from the others on the island: he has no Talent. With many "Talented" teenagers around him, Nanao is often a target for bullying, but even so, he still strives to complete his training. Soon after, two transfer students, the mysterious Kyouya Onodera and the mind-reading Nana Hiiragi, join the class. But just as everyone starts blending as comrades-in-arms, mysterious disappearances begin to threaten the class's entire foundation. [Written by MAL Rewrite]

The world has become a slaughtering ground for the Crimson Denizens, mysterious beings from a parallel universe who thrive on the life energy of humans. These merciless murderers only leave behind scant remainders of souls called "Torches," which are mere residues that will eventually be destroyed, along with the very fact of the victims' existence from the minds of the living. In an ambitious endeavor to put an end to this invisible, hungry massacre, warriors called Flame Hazes relentlessly fight these monsters. One fateful day, Yuuji Sakai ceases to be a regular high schooler—he becomes trapped in a crevice of time and is suddenly attacked by a Denizen. Coming to his rescue just in the nick of time is a nameless hunter who seems no different from an ordinary young girl except for her blazing eyes and burning crimson hair. However, before Yuuji can learn anything more about his situation, he discovers that he has already been reduced to a Torch—merely a scrap of memory waiting to be extinguished. [Written by MAL Rewrite]

Short specials included on the BD/DVD volumes of "Sekai de Ichiban Tsuyoku Naritai!"

Hagiwara Sakura and Miyazawa Elena are the leading members of a popular idol group, Sweet Diva. One day, Elena is injured by the attack of a female pro-wrestler Kazama Rio during the recording of a TV program. Sakura gets mad at Rio and gives her a dropkick. To avenge Elena, Sakura enters the female pro-wrestling matches.