People used to call such unfathomable abilities "superpowers". Through the discovery of a certain particle during the end of the 20th century, however, the mystery surrounding these powers was solved, with them and their users now being referred to as "Astral abilities" and "Astral users", repsectively. Arihara Satoru is an ordinary person living in this extraordinary world. However, that is but a facade. Hidden beneath the surface, Arihara Satoru is actually an Astral user working as an agent under a secret organization! His newest mission: "Infiltrate this school geared towards Astral users as one of its students!" Along with his little sister, Arihara Nanami, he succeeds in the infiltration and blends in with the students there without a hitch, building a rapport with fellow classmates Mitsukasa Ayase and Nijouin Hazuki as well as upperclassman Shikibe Mayu along the way. Having not drawn even the tiniest bit of suspicion, his mission continues according to plan. --Or so he had hoped. Due to an unforeseen event, his true identity was revealed to Mitsukasa Ayase! But the revelations didn't stop there; Ayase's own big secret was also revealed: What do you know! Her chest was padded! The two now held each other's unspeakable secrets within them. And with that one encounter, their fate would be forever changed--

Protagonist Takumi Kazuya who contributes parallel world erotic fantasy novels was soaked to the bathtub at home. [It enters till when stupid older brother] Younger sister aiming at the erotic manga artist to the elder brother who is soaked to the hot water foreverloses her temper, is the cause that gives MAX temperature to the bath, the bath heater drives recklessly, the large explosion is awoken. And then the sense that the body drops to the exit of white light. It falls among the hot water, Kazuya soaked to hot water again as water column is raised loudly. However... it is different from the bath at home soaked some time ago, moreover the stark naked pretty girl were turning the shocked expression to Kazuya in surroundings.

Haruta came to an old village where you couldn’t walk anywhere without seeing a cat. Due to a stroke of bad luck, he couldn’t stay at the apartment that he had reserved, but fortunately he was able to find a place to live in a small house called Nekohana-kan. The rent was free, but he had to agree to take care of the kittens. However, instead of cats there were three nekomimi girls waiting for him. As their master, he must support them so that they can live in the human world: that is, he must choose one of them to marry. Moreover, he had lost all his memories before that day.

Yuu’s older sister Maaya is quite popular, being both beautiful and friendly. He is proud of her, and likewise she cherishes him as her little brother. However, after a certain chance happening, her frequent teasings became naughty temptations. Her actions became increasingly bold and he had no choice but to follow along. However, there were no worries about their indecent relationship; instead, it was a enjoyable happy time with his dear onee-chan.