Oogami Island is normally a peaceful isle with lush green scenery, but is now a place of depraved wanton lust. The contagion Unknown - Level 4 has become epidemic. 3 girls, Hyuuga Natsu, Ochi Akari, and Hanazawa Airi find themselves trapped in a sports facility where they are assaulted by the infected.

Four years have passed since the terrible events narrated in Kansen 1 and 2, and the terrifying plague which depopulated the Tohoku region of Japan has been reduced to a mere (bad) memory, thanks to drastic quarantine measures coupled with an effective vaccine.
But the Unknown virus is not dead yet and soon, very soon, an unescapable doom will fall upon Wataru Ayase and his family and friends, trapping them inside the "Hell on Earth" madhouse which originally was their home city, Tokyo...

The story takes place in a small village. A girl, Ajisai, transferred to the village one month ago. The main character is Aoi. He always watches Ajisai being alone. One day, when he is at school, Ajisai tells him, "Let's play a game." Her offer changes everything around him.Ajisai, Kaede, Sanoou, and Sumire. The story goes as their thoughts mix with each other.

There is a beautiful princess, Janne, in a beautiful country. She has a special ability in sword technique and magic. The country is peaceful but monsters called ogres start to attack them. Janne takes an initiative and battles the ogres but her mother Celine is taken by them. Janne goes to rescue her mother by herself but she is trapped and caught by them. Janne is given a sexual training there and her body and spirit gradually change...

Kotarou was a seemingly shy and innocent boy until one day his sister, Hinako, discoveres he has a dirty secret. He had been secretly taking upskirt photos of her and her friends! After she confronts him, he reveals his true sadistic personality and begins to relentlessly harass and force his fellow female students into committing humiliating and degrading sexual acts.

Mao, who has a secret crush on Mikio, makes up her mind and invites him to go on a trip. The invitation gets accepted, and at the thought of the trip just for the two she feels elated.Mikio falls asleep right after installing himself in a seat opposite Mao in the train, helplessly spoiling the sport. She expands her expectations looking forward to upcoming events, though his seeming lack of interest dampens her ardor a bit.Despite her hopeful view, however, it turns out that her passion for...

Murakoshi Shinta is a student prone to wild delusions. He has kept this hidden all this while, living his gloomy and mundane life. One day, a tentacled alien parasite takes over his penis. Murakoshi complains to it that he is unable to walk around outside, what with his groin exposed, but the alien assures him that no one will notice as it has the ability to cloud people's minds. Thus, Murakoshi utilises that ability to satisfy his desires.

A spirit who takes the form of an attractive male is attacking many female students at a school. Two students discover that the only way to free him from his wandering around Earth is to have him fulfill his desire and so they decide to take a hands on approach and make him rest in peace at last.

In an old Western-style hospital, a forbidden story will be set in place. Takumi's deep awakened by the accident, the voices of the past, "the voice" can be seen wearing a strange ability. And, nurses and the fantastic scenes of invisible.

Akira Segawa is a "normal" high school student. One day he is caught masturbating by his older sister, Yuu Segawa, she then proceeds helping him to relieve his needs. Later that day Akira tells Yuu that he has some sort of unknown sickness. Yuu then decides to consult with a doctor, Tachibano Kimiko. She explains that the only cure for Akira's sickness is to have sexual intercourse with him. Thus starts the new sex-filled life of Akira Segawa with his sister, doctor and childhood friend...

After his grandpa's death, Katsuragi is contacted by the family at the estate where his grandpa worked as a butler. The family asks him to work there as a butler to replace his grandpa. It turns out, his grandpa was the caretaker of the daughter, who is the same age as Katsuragi, so he will now be in charge of taking care of her. When he is asked to take a bunch of boxes to her room, he walks in on her masturbating. How will she react?.

Igawa is gradually growing closer to Yano, a cute girl with glasses who is also an extreme fujyoshii. Fukuhara Shinobu, the class representative, is a childhood friend of Igawa and has secretly loved him for a long time. She is a loud-mouthed tsundere who likes to shave her pussy.Stupidity ensues after a few drinks, as Yano suddenly challenges Fukuhara to a game of "hard play". The two girls form an agreement to have sex with Igawa, who is now put in the enviable position of having a...

Yohei lives a peaceful life with his mother Kaho, and cousin Fumika. One day, Kaho suddenly confesses to Yohei that she is actually not his mother by birth. Although this depresses Yohei, Kaho assures him that he can continue living with her and Fumika, whom he has always treated as a sister, as if nothing has changed. However, a woman claiming to be Ikue, younger sister to Yohei's actual birth mother, moves in next door and asks that Yohei moves in with her. While Yohei is in a state of...

Linna is a SWAT officer who is faced with a series of bizarre murders. The victims are often found eviscerated and slashed, as if by huge claws, their flesh torn asunder. Then, a new string of crimes begin - the murders are similar but the targets are all men, seemingly seduced, then ambushed and brutally butchered. At about the same time, Linna's best friend, a beautiful stripper named Kata, has begun acting very strangely. Linna races to crack the case before her boyfriend becomes the...

* Based on a game by Guilty.Mochidzuki Yuuki and company are cut-off during a trip to an island training camp when civil war erupts. Just as the ship carrying the teachers leave to summon help, it is attacked by unknown persons and sunk. With nobody to rely on and provisions dwindling, the survivors split into factions and must look to their own survival. In return for the boys' protection, the girls are subject to all manner of disgrace...

Shun is the only male teacher at Kyoukasen Girls' School, a well-known high class school also known as the "Water School" since it is situated in a forest and there is a lake on the school grounds. It is a place to heal the wounds of those girls who are hurt. He meets girls who shut off themselves from the world, those who don't have confidence in themselves, those who are still traumatized by their past. He decides to help them move forward with their lives.

Musashi had come back to his village again. He had lost his memory about the four princesses who had been his childhood friends, and he'd also forgotten that he'd had sex with them. Even though he'd lost his memory, the familiarity of the village and his grand mother's house helped him remember. He was welcomed at his grandmother's home and met a girl named Tamamo. She said she was his childhood friend, but he couldn't recall her at all. At night, a strange smell lured him out, and he did...

While walking on a beach alone, young Takuya has a vision of a girl calling him "papa" and putting a ring onto his finger. Soon thereafter he discovers that the ring gives him the ability to instantly travel not only in space but even in time. He also discovers that the beautiful women around him, from his classmates to his own step-mother, know much more than they let him know... and that all of this somehow relates to his late father's scientific research.

The Protagonist's life takes a drastic turn when his new huge-breasted neighbor, Anette-san, introduces herself. Because he is a man of no shame and blatant frankness, he begs Anette to fulfill his lifelong dream, to have sex with her. As a meek woman, Anette can hardly say no, and he wastes no time in deflowering her. As he becomes aware of his advantageous position, he reveals himself to be sexually unsatisfiable and reveals his intent to impregnate Anette

One year has passed since the Chaos Arena was destroyed, Asagi and Sakura were presently on an abandoned street on a man-made island that floated on top of Tokyo Bay. It was an enormous box-shaped island built by the government and referred to as "Tokyo Kingdom."There was hope that it would become a second city center floating at sea, but it had failed to attract businesses.The only way of getting to and from the island was through Honshu Island over the 10 kilometer Tokyo Kingdom bridge...