Professor Pain

Ao Horie's father, a popular erotic fiction author, chose Ao's name because A stands for “apple” and O stands for “orgy”! Desperate to escape her father's legacy and get into a prestigious university, Ao devotes herself to studying instead of pursuing romance. She has no time for boys, but there's just one problem: Kijima, her handsome and popular classmate, just confessed his love to her! And to make matters worse, she can't stop thinking dirty thoughts about him! Looks like escaping her father's influence will be harder than she thought...

Male student Souta Tsukishima begins working at his family's public bathhouse as a back washer. While concealing her true identity, Souta's classmate Aoi Yuzuki visits the bathhouse. A relationship between the two begins to develop when Souta washes Aoi's back.

Once most students are done with high school, they leave and never come back. However, at 25 years old, Hana Natori finds herself in the role of a student once more at her aunt's request. Since Hana's cousin, Kaho Miyoshi, refuses to go to school, her aunt begs Hana to take Kaho's place, since the two of them are practically identical. But as luck would have it, she is recognized by Okito Kanie—an old classmate from her days in high school—who is now a teacher! With her cover blown, Hana assumes Kanie will expose her secret. But when he suddenly kisses her, she soon learns he has other ideas.

When Mafuyu Oribe and her adopted sister Tomo rescue a strange wounded man, they have no idea what they’re getting involved with or what the consequences will be. Alexander Nikolaevith Hell is an Iron Qwaser, one of many opposing factions of super-warriors.