Masamichi Akita, a high school student whose motto is to live wisely, who meets Setsuna Rikudou, a high school girl with a violent supremacist attitude.

Akita is saved by Rikudou when he is tangled up with a delinquent, and is attracted by her overwhelming strength, asks her to teach him how to fight. However, Akita is devastated by Rikudou, who asserts that “violence is the only rule in this world”.

Akita's encounter with Rikudou leads him into the world of “violence”.

Because he did not pass his college entrance exam, Kagami Kyosuke cannot stay close to Kojo Hikari, the love of his life. So instead he gets a part-time job near her university and buys an old camera since Hikari is passionate for photography. But as it turns out, this camera also possesses a secret which will get him involved in all sorts of embarrassing and awkward situations, especially with Botan Oshikiri, his senpai and co-worker. How will Kyosuke's life play out now?

Shota Iijima picked up erotic books during his childhood and suffers from a severe foreign sister fetish.

Thereafter, from the years between his age of 12 to 15, he masturbated 999 times. For his 1000th round of masturbation, he had been transferred to a different world.

And Shota is sold as a slave.

A paradise for women and hell for men… Valhalla, the penis mansion.

People called “challengers” are gambling their life trying to escape from The 100 Story Tower to win 10 billion yen. But what will happen when Tatsuki Kuroumi awakes at this tower without remembering anything about his prior life, including entering the tower as challenger?

In a world where the demon lord had been defeated and peace had arrived, Rex the magical doctor ran a clinic. But the patients brought in were all beyond saving compared to the world itself, people who'd XXX slimes or stuck their peens into man-eaters!? An otherworld perverted medical comedy begins!!

One day, Sanada Shirou, who works for a black company, is transported to another world. Using his "creation magic", an ability he gained when transported, he opens an inn and is supposed to lead a slow life, but this other world is a little strange?! It is a world where women are overwhelmingly dominant, where women do dangerous work and battle, and men are powerless and are protected! The daily life of entertaining (in many ways) the women of this other world begins...!

Web novel: https://kakuyomu.jp/works/1177354055503576578

Be spoiled rotten as a little brother by 「Heart-throb」-deficient older sisters!?

Touri, a college student searching for his older sister whom he was separated from 10 years ago, discovers that his admired senior, Sara, is a former magical girl, and that his sister was once a magical girl as well.
He continues his search for his sister with Sara’s help, but it seems the magical girls who have become “older sisters” can only draw magical power from heart-throbbing romantic excitement...?
The harem romance comedy featuring a former magical girl “older sister” and her “little brother” begins!!

What happens when next door to Fujiwara, an upcoming mangaka, moves Yuuki, who was his teacher back at high-school and first crush? Yuuki, a married woman now is starting a new life in the city but her husband is always away on business so she finds comfort in the company of her former student but what she doesn't realise is that Fujiwara can listen to everything happening in her apartment through the building's thin walls.

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.

Kosuke found himself in a whole different world. WHAT?
Standing there with the wilderness to the east and a forest to his left, he decided to make good use of the occurrence, and tests his knowledge, to where he finds this amazing crafting ability, just like the games from his orginal world!

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.

Set on a solitary island in the distant sea, a dangerous school life begins!

Kaoru Jahana, a boy who aspires to become a true man, begins his high school life on a solitary island in the sea. There, he meets a charming girl, Kanra, who is actually a demon who feeds on men's spirits...and it turns out that all the women on this island are the same demons!?

Na Hae-soo's life unravels when her husband betrays her with an affair, leaving her burdened with debt and losing their child. In a devastating blow, she witnesses him with a younger woman. Broken and despondent, Na Hae-soo feels her life crumbling around her. However, a mysterious young man unexpectedly enters her life, asking to be taught about adult love. His vulnerability and sincerity begin to stir emotions within Na Hae-soo, challenging her to reconsider her path forward.

"Kouji-kun, I want to see you have sex with another girl."

Even though this will drive my mind and body further into a corner, I just can't hold back my feelings of wanting her to love me...

(Source: Ganma)

When the Devil King announces his retirement, he calls forth his two sons, Yomi and Sora, to give them each a quest. Whichever of them finds a pure Yamato maiden within a year would inherit the throne of the Devil King, while the other would die. Thus begins Sora's sex-fuelled adventure to find a woman that can satisfy his father...
(Sakigake!! Otokojuku Wiki)

While on his way home from an interview, unemployed, unmotivated, jaded 18-year-old Inumata Shinogi encounters the beautiful lady and evil spirit Yaergnacht Finsternis. She demands him to either marry her or die on the spot. He must command the battle against enemies of humanity, the apostles of God (Highlanders), and save the world with his wife!!

The story begins with the protagonist, Wakou Ichiro, who decides to return home early from work to celebrate his second anniversary with his wife. But, when he opens the door of his house.... He finds his wife cheating on him! Although the marriage was short-lived, his life changes again when suddenly, a certain woman appears in front of him? Thus begins a new story, a new erotic comedy!

Lucas has a hard life. In his mid-thirties, a mixture of failures has left him old and crippled, playing pack mule to a couple of young adventures.

Then one day, he pulls a magic sword from a stone that tells him he has been chosen to become a hero. Given a youthful form, Lucas must use the power of the sword to vanquish evil and attain a massive harem.

Before you ask, it’s not isekai because he’s been in this world from day one. It is wish fulfillment, though, so in the end it’s basically the same thing.

In an era where one in every twenty people awakens to a "special ability," Hiroto Takigami is a weak ability user who can only communicate with spirits. However, for some reason, his stepsister Rei, the most powerful ability user, harbors deep hatred toward him. The moment he graduates from an ability training institution and gains full control over his power, Rei kills him. With only one year left to live—his "remaining lifespan" set—Hiroto falls into despair. Just then, a certain spirit appears before him, revealing an unexpected secret about his ability...

Having forgotten his keys, Tamao Hiroi a high-school student, returns home using the back entrance and is surprised to find a stranger in his bed… Soon he realizes this is no stranger but Ran Homura, one year younger, softball ace and one of the most beautiful girls at school! Hiroi watches her masturbating on his bed and instinctively does the same peeking through the glass door. He is soon found out though and a strange 'master/slave' relationship begins!