Yuuta Hibiki wakes up in the room of Rikka Takarada and notices two things: he has no memories, and he can hear a mysterious voice calling his name from a nearby room. On further inspection, he finds a robot—which introduces itself as Hyper Agent Gridman—behind the screen of an old computer. Much to Yuuta's surprise, Rikka cannot hear Gridman, nor can she see the ominous monsters looming over a thick fog as it envelopes the town outside. Another giant monster materializes in the city and proceeds to wreak havoc. Amidst the confusion, Yuuta is once again drawn to the old computer and merges with Gridman. Suddenly, he appears in the middle of the battle and is forced to fight the monster. Together with Rikka and fellow classmate Shou Utsumi, Yuuta forms the "Gridman Alliance" to defeat the monsters plaguing the city and find whoever is responsible for their emergence. [Written by MAL Rewrite]

Makoto Niwa meticulously tallies the amount of positive and negative youthful experiences he engages in as if to grade his own life. When his parents go overseas, he moves to a new town to live with his aunt, welcoming the change and ready for a fresh start. However, as ordinary as he had imagined his adolescence to be, he could never have taken the existence of an enigmatic long-lost cousin into account. Upon moving into his aunt's house, he discovers the cousin he never knew about: Erio Touwa. Despite being Makoto's age, she couldn't be more different: Erio chooses to wrap herself in a futon all day rather than to go to school. She even claims to be an alien, and with a speech pattern and personality to back it up, any chance of Makoto's dreamt-of normal life is instantly tossed out the window. As he meets a string of other eccentric girls in town, Makoto must face the possibility of seeing his youth points in the red. However, he might be surprised by how thrilling an abnormal youth can be. [Written by MAL Rewrite]

"Alpha Stigma" are known to be eyes that can analyze all types of magic. However, they are more infamously known as cursed eyes that can only bring destruction and death to others. Ryner Lute, a talented mage and also an Alpha Stigma bearer, was once a student of the Roland Empire's Magician Academy, an elite school dedicated to training magicians for military purposes. However, after many of his classmates died in a war, he makes an oath to make the nation a more orderly and peaceful place, with fellow survivor and best friend, Sion Astal. Now that Sion is the the king of Roland, he orders Ryner to search for useful relics that will aid the nation. Together with Ferris Eris, a beautiful and highly skilled swordswoman, Ryner goes on a journey to search for relics of legendary heroes from the past, and also uncover the secrets behind his cursed eyes. [Written by MAL Rewrite]

Denizens from the Crimson Realm continue to infiltrate Misaki City and steal life energy from humans. To combat this threat, Flame Hazes are tasked with saving humans from losing their existences. But while it is a Flame Haze's duty to protect humans, Shana—the "Flame-Haired Burning-Eyed Hunter"—seems to be focusing her attention on one human in particular: Yuuji Sakai, a teenage boy who was unwittingly dragged into the fight between Crimson Denizens and Flame Hazes. Since her first encounter with Yuuji, Shana has started to see him as more than just a friend. In fact, Yuuji wonders if Shana might have revealed her feelings to him once before, but it is difficult for him to confirm due to her hot-and-cold personality. Nonetheless, their days pass like any other, until a new transfer student arrives at their high school—one who bears a striking resemblance to an old enemy. Yuuji and Shana have no time to dance around their feelings for each other; while their adversaries from the Bal Masqué organization plan their next attack, the two must keep their guard up as they explore the origin behind the coveted magical object within Yuuji's body, the "Midnight Lost Child." [Written by MAL Rewrite]