In the distant future, humanity has been driven to near-extinction by giant beasts known as Klaxosaurs, forcing the surviving humans to take refuge in massive fortress cities called Plantations. Children raised here are trained to pilot giant mechas known as FranXX—the only weapons known to be effective against the Klaxosaurs—in boy-girl pairs. Bred for the sole purpose of piloting these machines, these children know nothing of the outside world and are only able to prove their existence by defending their race. Hiro, an aspiring FranXX pilot, has lost his motivation and self-confidence after failing an aptitude test. Skipping out on his class' graduation ceremony, Hiro retreats to a forest lake, where he encounters a mysterious girl with two horns growing out of her head. She introduces herself by her codename Zero Two, which is known to belong to an infamous FranXX pilot known as the Partner Killer. Before Hiro can digest the encounter, the Plantation is rocked by a sudden Klaxosaur attack. Zero Two engages the creature in her FranXX, but it is heavily damaged in the skirmish and crashes near Hiro. Finding her partner dead, Zero Two invites Hiro to pilot the mecha with her, and the duo easily defeats the Klaxosaur in the ensuing fight. With a new partner by his side, Hiro has been given a chance at redemption for his past failures, but at what cost?

At Suimei High, the Sakura-sou dormitory is infamous for housing the school's most notorious delinquents. Thus, when the relatively tame Sorata Kanda is transferred to the dorm, escaping this insane asylum becomes his foremost goal. Trapped there for the time being, he must learn how to deal with his fellow residents, including bubbly animator Misaki Kamiigusa, charming playboy writer Jin Mitaka, and the ever-reclusive Ryuunosuke Akasaka. Surrounded by weirdness, Sorata frequently finds respite in his interactions with his one normal friend, aspiring voice actress Nanami Aoyama. When Mashiro Shiina—a new foreign exchange student—joins the dormitory, Sorata is instantly enraptured by her beauty. Underneath her otherworldly appearance, Mashiro is an autistic savant, capable of world-renowned brilliance in her art, yet unable to perform simple daily tasks. After Sorata ends up in charge of taking care of Mashiro, the two inevitably grow closer, with Sorata's initial desire to escape the dormitory becoming a forgotten goal. Despite their eccentricities, every resident is incredible in their own field, leaving Sorata to contend with his own lack of any particular skill. With brilliance all around him, he thus strives to become an equal to their talent. Revolving around the hardships and joys of its colorful cast, Sakura-sou no Pet na Kanojo is a heartwarming coming-of-age tale of friendship, love, ambition, and heartbreak—through the lens of an ordinary person surrounded by the extraordinary.

On a rainy morning in Tokyo, Takao Akizuki, an aspiring shoemaker, decides to skip class to sketch designs in a beautiful garden. This is where he meets Yukari Yukino, a beautiful yet mysterious woman, for the very first time. Offering to make her new shoes, Takao continues to meet with Yukari throughout the rainy season, and without even realizing it, the two are able to alleviate the worries hidden in their hearts just by being with each other. However, their personal struggles have not disappeared completely, and as the end of the rainy season approaches, their relationship will be put to the test.

Chiyo Sakura is a cheerful high school girl who has fallen head over heels for the oblivious Umetarou Nozaki. Much to Chiyo's confusion, when she confesses to her beloved Nozaki, he hands her an unfamiliar autograph. As it turns out, the stoic teenage boy is actually a respected shoujo manga artist, publishing under the pen name Sakiko Yumeno! A series of misunderstandings leads to Chiyo becoming one of Nozaki's manga assistants. Throughout the hilarious events that ensue, she befriends many of her quirky schoolmates, including her seemingly shameless fellow assistant, Mikoto Mikoshiba, and the Prince of the School, Yuu Kashima. Gekkan Shoujo Nozaki-kun follows Chiyo as she strives to help Nozaki with his manga and hopes that he will eventually notice her feelings.