Based on the erotic game by Marine.
After a long absence, Shunsuke returns home at the invitation of his older sisters. He learns that his sisters suffer from a rare condition: they have abnormally strong sexual desires resulting from a disease. Now, Shunsuke must do whatever he can to improve their health.

Based on the game by Buruge on Demand (label of Blue Gale).
Naoto, a young guy with a thing for busty women, and he is the luckiest man in the world:
Ayane, a busty babe he’s known for all his life, has a thing for him and lets him have sex with her anytime he wants, and to spice it up, Chika, another one of his booby childhood friends, has just a big a crush on him too. When she says to him, “My breasts belong only to you,” there’s no way any guy would resist. There’s now only two things that will be hard Naoto’s life, one of them is choosing between two gorgeous booby hotties!

Based of the game by Candy Soft. Summary of the game:
The Hanabishi family and Hidaka family are next door neighbors. The fathers of both households could be called best friends, so they all get along like one big happy family. In particular, Hidaka family’s only son Kouki was raised lovingly by the four Hanabishi sisters like he was their own brother. One day, the Hanabishi and Hidaka parents were preparing for a long term overseas business trip together. Kantaro Hanabishi had only one problem holding him back from the trip; leaving his four daughters behind in Japan. “Leave it to me. You can rely on me to watch over them!” As a result of Kouki’s casual announcement, both parents happily departed on their trip. “Ooh, how reliable! That was what I was waiting to hear!” Between both of the parents, they had arranged for one of the four sisters to become Kouki’s fiance. After Kouki’s graduation they would continue discussion of it further, but this recent event gave a chance to accelerate their plan.
Thus, all summer vacation Kouki will spend time alone under one roof with all four of the Hanabishi sisters.
The eldest daughter Yurina: Despite being good at her job, While at home she lazes around and makes Kouki work hard. The second born daughter, Momone: Absolutely adores Kouki, and does nothing but spoil him. The third daughter, Saori: She does all the housework, and although she is like a maid she prefers it to going outside. The youngest daughter, Anzu: Has no reservation in calling Kouki her personal play toy.
Each of them have their own motives doing anything they can; at times even tempting him into sexual situations, so they can draw closer to making the Kouki they love their husband. If Kouki ever chooses a bride, who will it be? The energetic life with the quartet of sisters is about to begin.

One week after losing his wife in an accident, the father of the Makino family finds himself thinking the wrong thing about his four lovely daughters. When the rebellious Natsume gets into trouble at school, it’s time for daddy dearest to administer some discipline of the sexual variety. Soon, he’s giving the same treatment to motherlike Akira, over-achieving Haruka, and sickly Fuyu. Whether they want it or not.

Even though hes young and quite small, he is HUGE where it counts. All the older girls in his life seem to be enchanted with the idea of this littla shota with a giant package!

Based on an erotic game with the same name by Lune.
A Horse-man, a Snake-Woman, Orcs. Shoujo Senki Brain Jacker is captured and brutally raped by each. A follow-up story to Shoujo Senki Soul Eater.

Private ‘lessons’ with sensei, in glorious 3d pov.
Three different role play settings:
Bad Karma – Hotaru doesn’t want the D, aka raep lol
Good Karma – vanilla; sex with sensei on desk, in school, in broad daylight, the usual.
Great Karma – Hotaru is the naughty one.

After the disappearance of her sister and finding out she had joined a suspicious enlightenment group seminar, Riko enlisted herself into the course to find her but the only way to reach the same course as her was to rank up and the only way to do so was to help others release… that being through sex.