Kazunari Usa is a high school freshman who will start living alone due to his parents now working in a different area. Excited for his new independent life, he hopes to go about his teenage days without the worry of dealing with any strange people, but as he soon discovers, his new boarding house Kawai Complex is far from ordinary. The various tenants at Kawai Complex are all quite eccentric characters. Shirosaki, Kazunari's roommate, is a pervert and masochist; Mayumi Nishikino, a borderline alcoholic office lady, hates couples because of her unfortunate luck with men; and Sayaka Watanabe, a seemingly innocent college student, enjoys leading men on. Shocked with the lack of decent individuals at his new residence, Kazunari is about to leave when he runs into shy senior student Ritsu Kawai and finds himself slowly falling in love with her.

In the distant past, Miguel, the God of Destruction, was sealed inside the knight who ruled over light and darkness, Sturmhurt. Alongside the knight was Gestöber, who accompanied him through countless battles. In the present day, destiny causes them to reincarnate as Kabuto Hanadori and Seri Koyuki, two classmates. Their reunion should be a joyous moment, if not for the fact that these fantasied heroes are just products of Kabuto's delusions. As the fictional Gestöber, Seri finds himself in various embarrassing situations due to Kabuto's antics that sometimes grow out of his control. Moreover, his classmate Utsugi Tsukimiya joins the fray with his absurdly accurate mind-reading abilities, slowly destroying Seri's social life. Seri tries hard to stay away from them, refusing to acknowledge their shenanigans, however with Kabuto's chuunibyou and Utsugi's unpredictability, he is only bound to be swept by the craziness coming his way.

Under the doctrines of Quirk Doomsday Theory, the ideological group Humarise is convinced that all humans with quirks are diseased and must be eradicated. In order to rebuild the world, the group's extremists have constructed a lethal device known as a Trigger Bomb that causes people with quirks to lose control and die. Their leader, Flect Turn, evades capture from the Pro Heroes deployed around the world. During his work study in the country of Otheon with Japan's number one Pro Hero, Izuku Deku Midoriya is accused of a crime he did not commit. Unintentionally involving Roddy Soul, a local, Deku soon finds himself on the run with the boy. It is now up to Rody, Deku, and Deku's classmates to stop the Trigger Bomb plot set in motion by Flect, all while eluding the other persistent members of Humarise.

Kyoutarou Ichikawa may look like a shy and reserved middle school student, but deep within his heart is a bloodthirsty killer. His ultimate desire is to see his classmate Anna Yamada's beautiful face writhing in pain before he ends her life. But this fantasy may never come to fruition, as Ichikawa starts to see an entirely different side to Yamada. Often seeking refuge in the library, Ichikawa frequently runs into Yamada. It is during these encounters that Ichikawa realizes his model classmate is actually an airhead who can never read the room. As they spend more time together, the boy cannot help but feel not only a sense of endearment toward the very girl he wishes to murder but also a desire to protect her at all costs. Is it possible that this sudden change in Ichikawa's perspective could lead to something more?