Rosario + Vampire (2008)

Rather than take a more sensible approach to salvaging his grades in time for graduation, Alto summons a bit of otherworldly help. Only after does he learn he’s bound the legendary she-devil Vermeil into service as his familiar!

A door to another world stretches out before a boy who's been brutally bullied all his life. This alternate reality grants him access to all sorts of things, like cheat skills and a portal that lets him travel between his old and new worlds! Can this class loser turn his life around back home...?

Ko's new companion, Nazuna, could offer him dark gifts and a vampire's immortality. But there are conditions that Ko must meet before he can sink his teeth into vampirism, and he'll discover just how far he's willing to go to satisfy his desires.

Rai wakes up from 820-years long sleep and starts his new life as a student in a high school founded by his loyal servant, Frankenstein. But his peaceful days with other human students are soon interrupted by mysterious attackers known as the "Unions".

A vampire queen and a human girl join forces against all odds in search of “paradise” — a place where humans and vampires peacefully coexist.

High school student Michio Kaga was wandering aimlessly through life and the Internet, when he finds himself transported from a shady website to a fantasy world — reborn as a strong man who can use "cheat" powers. He uses his powers to become an adventurer, earn money, and get the right to claim girls that have idol-level beauty to form his very own harem.

Hajime Nagumo and his high school class are suddenly summoned to a fantastical land as heroes. But while most of his classmates have powerful stats and abilities, Hajime does not. Underappreciated and unprepared, he tumbles into the depths of a monster-infested dungeon where voracity and sacrifice are his only options. To thrive in this savage world, he’ll have no choice but to welcome the abyss.

The story takes place in an age where "Ajin" (demi-human), more casually known as "Demi," have slowly started to become accepted into human society. Tetsuo Takahashi is a biology teacher who ends up teaching three such Demi, hoping to understand more about them while also managing to catch their attention.

Fourteen-year-old Iruma Suzuki has just been abandoned and sold to a demon by his irresponsible parents! Surprisingly, the next thing he knows he's living with the demon who has adopted him as his new grandson and has been transferred into a school in the Netherworld where his new demon grandfather works as the principal. Thus begins the cowardly Iruma-kun's extraordinary school life among the otherworldly as he faces his true self, takes on challenges, and rises to become someone great.

High school student Hiiragi Seiichi is bullied by his classmates for being a "loser." One day, his entire school is suddenly transported to a video game-like world of swords and sorcery. When he accidentally eats "the Fruit of Evolution," his life as a successful "winner" begins.