In the 21st century, the rapid development of the human society has broken the equilibrium between the realms of human, immortal and monster. Su Moting is an ordinary working girl living in the human world. She is also the "son of the immortal and the monster". Driven away from home by her parents, Su teams up with an immortal and a monster, and the three of them start their hilarious daily life.

Shungo Ninomiya is just an ordinary, run-of-the-mill high school student who lives at home with his older sister Ryoko—at least when she's not away doing her job as a mercenary. However, Shungo's life ceases to be normal the moment a cute girl named Mayu Tsukimura descends into the middle of his school's campus in a military-grade helicopter. It turns out Ryoko sent this girl, along with her older brother Mikihiro, to live at the Ninomiya household. But the newly-arrived siblings are a little special: Mayu is, in fact, a succubus and her brother, an incubus! And as if the circumstances are not problematic enough, Mayu is crippled with androphobia—the fear of men—and it's up to Shungo to help her overcome this at the behest of his sister. Ryoko plans to force Mayu to be closer to Shungo, and to do this, she’ll employ some questionable methods such as having them share the same bed and even take baths together. The situation further complicates when student council president Reika Houjou arrives as the new maid of the Ninomiya family, and she will stop at nothing to thwart Shungo and Mayu’s sexually-geared training. With the sudden arrival of all these oddities, Shungo's ordinary life is about to be thrown into utter turmoil. [Written by MAL Rewrite]

Fortune Arterial's story revolves around the male protagonist Kohei Hasekura, who transfers into a prestigious public school in the style of an English six-year school encompassing junior-high and high school students. The school is on an island named Tamatsu Island off-shore from mainland Japan, and the only way to get there is by boat. Soon after transferring, he discovers that one of the student in the class next door to his, Sendo Erika, is in fact a type of vampire.

Tatsuko of class 5-1 is really excited about the upcoming school sports festival, her proposal for a new "Eel Scooping" event is less than enthusiastically received though, especially by Suzuka. Illya mentions the main event dance to Miyu, and as teacher Taiga Fujimura points out, it entails a huge reward, but will require quite a bit of practice. And so the close friends: sarcastic Nanaki, level-headed Suzuka, excitable Tatsuko, energetic Illya, shy Mimi, and reserved but athletic Miyu are off to win the dance event for the honour of their class and for Fujimura, who seems to have some saucy bet going on that she most definitely needs to win, or so the girls misunderstand. (Source: AniDB)