Variable Geo Neo (2004)

The story takes place in Japan in the early 21st century, in an alternate reality where the Tokugawa Shogunate has remained in power. In this reality, student councils are tasked with oppressing schools. Yagyuu Muneakira is a high school student who rebels against his student council with the help of girls who've had the names of famous samurai heroes passed on to them.

After inheriting his late grandmother’s failing café, Hayato sees it as a bother and plans to sell it for a quick buck. Until he discovers five beautiful girls staying there! When they beg him to keep the café open, Hayato reluctantly gives in. Can he manage the seaside shop while learning to live with these unruly women?

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.

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.

Kaede Honjou is invited by her friend Risa Shiramine to play a virtual reality MMO game with her. While Kaede doesn't dislike games, what she really, truly dislikes is being in pain. She creates a character named Maple, and decides to put all her points in VIT to minimize pain. As a result, she moves slowly, can't use magic, and even a rabbit can get the best of her. But as it turns out, she acquires a skill known as "Absolute Defense" as a result of her pumping points into VIT, as well as a "Counter Skill" that works against special moves. Now, with her ability to nullify all damage, she goes on adventures.

Every few years, beautiful female warriors from across the land compete in the Queen's Blade Tournament to become the ruler of the land. It's a series that loves violence as much as it hates clothes and complicated plots.

Hida Kizuna possesses the HHG (Heart Hybrid Gear) ability, but it is not strong enough to make him particularly important. His older sister calls him to transfer to a strategic defense school, where many of the students (many of which are large-breasted girls) use their HHG abilities to fight invaders from another world while wearing extremely skimpy pilot outfits. Kizuna's fighting ability doesn't measure up, but his sister has another plan—apparently having erotic experiences with Kizuna will allow the girls to replenish their energy or power-up. It looks like his new school life is going to be full of embarrassment.

16-year-old Hayate is really down on his luck. Because his unemployed parents are good-for-nothings who waste what money they have on gambling, Hayate had to start working at a young age to help out his family. Although such experience has made him inhumanly fast and tough and skilled at things boys aren't normally skilled at, it has also left him in an awkward position, as his parents have racked up such a huge gambling debt that they have sold Hayate to the yakuza for the value of his organs. In a desperate attempt to avoid that fate, Hayate decides to become a "bad guy" and kidnap someone to be held for ransom, but his efforts to do so are mistaken as a confession of love by the girl he targets. When he helps save the (as it turns out) ultra-wealthy 13-year-old Nagi from real kidnappers, she takes him in and gives him a job as her new personal butler (and love interest) until he can pay off his debt. But Hayate is more attracted to Nagi's beautiful teenage maid Maria, and head butler Klaus is initially disapproving of a boy with such a poor look. And then there's Nagi's pet Tama, who is also a force to be reckoned with.

Jin Mori has proclaimed himself the strongest high schooler. His life changes when he's invited to participate in "God of High School," a tournament to determine the strongest high schooler of all. He's told that if he wins, any wish he makes will be granted... All the participants are powerful contenders who fight their hardest for their own wishes. What awaits them at the end of the tournament? A chaotic battle between unbelievably strong high school students is about to begin!

In a world bursting at the seams with moe monsters and humanoids of the horned sort, which brave heroes will take it upon themselves to review the beastly babes of the red-light district? Can only one be crowned the ultimate title of best girl? Behold the most tantalizing of trials.