Kanae is a girl who is struggling to fit in with the popular clique at her high school. Because she had been bullied in middle school, she has developed an acute inferiority complex that had led her to engage in compensated dating in order to feel wanted.

In comes Hiroshi, a high-school baseball star who became drawn to her after finding her crying during a group date at a karaoke bar. Thus begins an unhealthy relationship between a mentally unstable high-school girl and a jock.

This shitty world that's nothing but a trashy game, he and I will definitely escape it together.

So, all these annoying women trying to take advantage of him are just a nuisance. What's worse, it seems like he's beginning to have some feelings for them.

That's why, for his sake, I'll eat them up first.

But, just what is this power...?

Nezumi is a girl who was raised as a hitman by the yakuza and grew up not knowing human love. An ordinary young man, Ao, knows nothing. They fall in love and start to live together, but the evil hand is close at hand.... This is a story of first love, so cruel and so sad.

From MangaHelpers:
This manga tells the story of Hatshepsut, a woman who reigned successfully over Egypt for many years. The story begins when she is a young woman, marrying her half-brother Thutmose II and thus ensuring his rise to Pharaoh. Hatshepsut is a woman with a strong will, who is not going to accept the restrictions others might try to place on her as a woman.

Seven women, one man, a suspenseful harem story!

During a class reunion, the school became an enclosed dimension without warning. Yelling and screaming brought no response. 26-year old unemployed Haruka Sato has to survive by cooperating with seven of his former classmates. Soon, the extreme conditions began to eat away at their sanity, and Haruka's hidden desires began to take hold.

One day at school, Youta Tada sees someone strange entering school. Out of nowhere this being appears next to him and makes him fall from the third floor! But before he hits the ground, he wakes up in a strange world where beings like dragons exist! Youta then meets a young paladin named Lumi and discovers that he is the only man on the entire planet, and also that its inhabitants are extremely 'weak' to his presence or more specifically, his touch. Would this be a paradise?

A prequel series revealing Goblin Slayer's past and the events that led him to become an adventurer with the sole purpose of exterminating all goblins from the world.

This is the legendary Go Nagai's breakthrough work. Harenchi Gakuen is an elementary school whose teachers and students are all perverts. Boys peep girls changing. Girls pull up their skirts and show off their panties. Actually, it's not as evil as you imagine. They're like cubs playing together. It's only pre-school eroticism, nothing sexual. In spite of that, Harenchi Gakuen became a sensation. Parents, teachers, and politicians hysterically attacked the comic's immorality.

Distributing thrilling videos in secret. A school game that puts life and death on the line.

A gate appears in Tokyo's Ginza district sometime in the 21st century. From the gate pours out monsters, knights from middle-age Europe, and other fantasy-like beings, and they kill many of the citizens of Tokyo. This event is known as the Ginza Incident.

The government sends a small group of soldiers from the Japanese Self-Defense Forces to the alternate world beyond the gate. Led by otaku soldier Yōji, they find that the villages in the world are being attacked by a dragon. An elf girl who is a survivor from the dragon's rampage joins the group in their travels across the dangerous new world.

10 years since he reincarnated in hell…Takamichi is troubled. With the “Incubus” power unlocking further to become stronger by having sex with women but his growth peaked. “I’ll move to a new area, wait for me beautiful women of the new world!” Sexy & violent pretty girl battle fantasy!

Circa 1937. A Japanese soldier in Manchuria meddling in the opium trade.

Magnus, a mage who always got yelled at “just shut up and follow my orders!” by the Hero because he was deemed “useless”. One day after getting fed up with his party he left, upon leaving he met a merchant that sold him a mysterious book.
And it turned out that the book which was written in the god's language was actually an ultimate encyclopedia book that had a lot of useful information on how to defeat the Demon Lord!
Thanks to that book, he was able to know about boss monsters' weaknesses and raise his level more efficiently, data about important people, and it even had info on complete gourmet spots in any city! Moreover, by using his wits and scheming mind, he's even able to outclass the hero party! With the ultimate encyclopedia in his hands, advance to the true route to defeat the Demon Lord!

Magnus wasn't chosen by destiny to be the hero. That's why, He's going to beat the Demon Lord with his own power and wits and save the world.

"I do not trust humans. They’ll betray you without fail.” Aur, the man who had obtained the ability and right to become the Maou at the end of his life of research. Summoning the succubus Lilu, he then sets out on creating his own domain, a gigantic labyrinthine dungeon… The misanthropic Maou taking on the world, the curtain rises on a dark harem fantasy!

Average high school student Mikagami​ Kouji is a hardcore gamer. One day he gets isekai'd and he only gets the skill "copy" which is apparently useless but we all know it's secretly OP or something. He's enslaved to be a gladiator by his summoner, the big booba, head priestess Zayd. He has to fight in the Colosseum and if he loses he gets raped.

By the time he opens his eyes, Kubota Tamotsu (34 years old) has been reincarnated into another world. Moreover, as a 6 years old slave with “Level 1 Barrier” skill. To surpass his limitations and become a powerful Barrier master Kubota begins a hellish training, full of obstacles and struggles. — From “Let’s Become a Novelist”, a new other world fantasy starts!

From MangaHelpers:
People have been created that are human-animal hybrids, and powerful businesses bet on the outcome of their duels. College student Nomoto Yuuya's casual acquaintances ask him to drive them around to pick up girls one day, which he soon finds out means by force. The girl they kidnap is an animal-human hybrid named Hitomi, who slaughters all of them except Yuuya. Hitomi is a honey badger, which has been called the most fearless of all animals. Now Hitomi is assigned to stay with Yuuya, for his protection.

Takemura wakes up after falling ill for 3 days and realizes the world has been overrun by zombies but for some strange reason he is not being attacked by them! What will he do now with this great power he has?

Tanaka was a salaryman who lived an average life. That life came to an end when he was 41 years old…or it was supposed to. But when he came to his senses, he was standing in a world that resembled ‘Medieval Europe’. There was no heating system, and food was eaten with your hands. On top of all that, pigs ran wild in the city…and what did the pigs eat? Shit. And in this harsh world, Tanaka would live his second life as ‘Varian De Lioncoeur’. Will this average salaryman be able to survive?

Links:
Web Novel: https://ncode.syosetu.com/n4662ec/ (Japanese)

After he and his entire class die on a field trip, Odamori accepts an offer from a mysterious man to be reincarnated. However his new job turns out to be that of a 'Slavemancer' with the power to dominate the minds of others and turn them into his toys, which he happily takes on. Soon however his evil actions lead to a Princess Knight (who turns out to be one of his previous, more popular classmates) being dispatched to apprehend him. But Odamori of course has something different planned for their reunion.