It's the Taisho era—a time filled with the scent of romance, and people's hearts are still filled with compassion. Unzen, Sukayu, Unohana, Oshamanbe, and Aso are all ordinary (?) male students at Binan High School, who spend their days lazing around in the clubroom of the do-nothing club Earth Defense Club, and live together in the Kurotama dormitory. One day, while the five are taking a morning bath at the Kurotama dormitory, they notice something slimy moving in the bathtub. When they finally manage to catch it, it turns out to be a talking Pallas's cat named Nuru! Nuru has come from the distant future with a serious mission to inform them that the Earth is facing an impending threat of destruction. While he says he wants to protect the Earth, he says he's only come to warn them of the crisis, and that it's up to the five of them to decide whether or not they want to fight for the Earth... Isn't this just an attempt to dodge responsibility? The Defense Club members are suspicious. If either is fine with you, I'll do it! That's more fashionable! Unzen enthusiastically says. The five decide to fight with free will, and Nuru transforms them into the Haikara Romantic Troupe using feline science. Meanwhile, a mysterious trio called the Bankara New Elite Squad are scheming in the shadows. They are plotting to take over the Earth. (Source: Official site, translated and edited)

Due to frequent misadventures with the supernatural and her hectic school life, Nene Yashiro can barely catch a break until Kamome Academy's annual sleepover event comes around. Nene is excited to blow off some steam with her best friend Aoi Akane and the rest of her class at the get-together. Unbeknownst to her, the sleepover falls on the same date as Urabon, when the line between the dead and the living gets distorted, allowing wicked spirits to come out to the surface. When an evil ghost is about to attack her, Nene is rescued by a mysterious figure: Shinigami, the Sixth Wonder that can trap souls using his flute. In that moment, Shinigami takes notice of Aoi and abducts her to use her as a sacrifice that will close the barrier for good. Joined by Hanako-kun and Akane Aoi, Nene must embark on a journey into the deepest confines of the world of the dead to save her best friend before it is too late.

After a disastrous romantic confession, Masamune Okumura finds solace in the fictional world of anime and manga. Now a second-year high school student and the president of the Manga Research Club, Masamune spends a peaceful existence watching the adventures of the angel Liliel, his favorite character. In the beginning of the academic year, Masamune’s life is turned upside down when he meets first-year student Ririsa Amano, a passionate cosplay practitioner. Despite Masamune's initial reluctance, the determined young woman manages to convince him to become her personal photographer for the production of a collection dedicated to their common favorite character: Liliel. As Masamune enthusiastically discovers the world of cosplay and photo editing, he is unexpectedly reunited with his childhood friend Mikari Tachibana, who has become a model in the hope of impressing her beloved upperclassman. Realizing that modeling is not enough to intrigue the hopeless otaku, Mikari decides to join the club and become a cosplayer herself, all to finally have a chance at winning Masamune's heart. However, Masamune's love for fictional characters may not be capable of extending to those who impersonate them.

Aimless daydreaming in high school is an ordinary part of growing up. But once graduation comes, suddenly there are bills to pay and a higher education to tackle. Even so, Midori Nagumo never quite stopped dreaming—even after entering college—as she still wants to have fun while ignoring her responsibilities. Contrasting Midori's recklessness is her supposed best friend Niikura, who is the complete opposite of Midori and has a goal of becoming a photographer after college. However, Niikura is often pulled into Midori's schemes, which leads them to meet Wako Izumi, a tenacious, yet airheaded classmate who is always taking pictures of things she finds fun. The trio ends up living together in the same apartment and attempt to navigate their lives in the city of City, where unexpected and out-of-the-ordinary things occur daily.