The story follows Iruma Suzuki, a 14-year-old human boy, who is sold to a demon by his parents. The demon, known as Sullivan, takes Iruma to the Demon World and officially adopts him as his grandson. He enrolls Iruma in the Babyls School for Demons where he is the headmaster and where Iruma quickly befriends the demons Alice Asmodeus and Clara Valac. However, Sullivan tells Iruma to never reveal that he is human since he will be eaten if anyone finds out. Iruma then vows to blend in during his time in the demon world, although he only stands out because of all the situations and adventures that arise.

Falling in love at first sight with a collapsible bicycle outside the station, Ami Kurata, first-year university student empties her account without a second thought and buys the bicycle. Now she enjoys weekend cycling trips with Aoi, her childhood friend, and Hinako, a senior at her university. "Owning a road bike may change your view of the world completely." Prompted by the comment, Ami purchased a road bike, and she is really impressed with the traveling performance. As soon as she places her feet on the pedals and presses down, everything about riding a road bicycle—the lightness of the pedal, the speed, the acceleration—is nothing like she has ever experienced. Ami's cycle life gets going with the new road cycle as her partner! (Source: Showgate, edited)

On his first day of high school at the formerly all-girl's Ousai Private Academy, Takatoshi Tsuda is called out for his untidy uniform by the student council president Shino Amakusa. In apology for delaying Takatoshi for his first class—and stating that the group needs a male point of view to accommodate the arrival of boys at the school—Shino offers him the position of vice president of the student council. Though unwilling, Takatoshi finds himself appointed as the newest member of the student council having yet to even step foot inside the school building. Takatoshi soon realizes that the other student council members who are more than a little strange: President Shino, who is studious and serious in appearance, but actually a huge pervert, fascinated with the erotic and constantly making lewd jokes; the secretary Aria Shichijou, who may seem like a typical sheltered rich girl, but is just as risque as the president, if not more so; and finally, the treasurer Suzu Hagimura, who may act fairly normal, but has the body of an elementary school student and is extremely self-conscious of it. Surrounded by these colorful characters, the new vice president must now work through a nonstop assault of sexual humor and insanity. [Written by MAL Rewrite]

It is the start of Takatoshi Tsuda's second year as the put-upon vice president of the student council and his sister Kotomi is entering school as a first year. New friends and double entendres are made. (Source: ANN)