In school trip to the nudist beach!!

Take a school trip to Nude Beach where this beach has rules for all visitors to be naked without dressing, and also men are forbidden to be aroused. However, if someone is aroused then someone will be given the opportunity to release his desire by doing pervert things in the tent. (Source: Nekopoi and Has Been Translated and Edited)

Gibomai

A renowned painter dies of heart disease while being married with Megumi, a woman much younger than he is. His son, Kyosuke, never liked that union and wants Megumi out of the house. Therefore Megumi proposes that Kyosuke can do anything he wants with her daughter Yuna, Kyosuke's stepsister, if he allows them to stay. Naturally, Kyosuke accepts. (Source: AniDB)

Furifure THE ANIMATION

Based on the erotic game by Noesis. Yui Kurahashi quarreled with her parents and ran away from home. As Yui walks around town, Yui meets a friend and Yui has been fooled into joining a dating site called Free Friends. Yui's just waiting for someone to contact her even though Yui does not know much about it. The main characters accidentally find it and its contacts. That night, they met in a city full of libido and.... (Source: Translated and Edited from Nekopoi)

Bible Black Origins

Based on the erotic game by Active. Twelve years prior to it's discovery by Minase, the origins of the magic book with dark,sensuous powers is revealed. Initially owned by a female student, Takashiro, who, along with other curious students form the first magic club on campus. The club begins to use the erotic spells to carry out favors for fellow students, and vengeance. After underestimating the powers behind the book, Takashiro is taken out of the picture, as a new leader guides the club towards a darker course, one that will force school newcomer Kitami to make a dire choice.

Anehame: Ore no Hatsukoi ga Jisshina Wake ga Nai

After school, Akira Sakagami is about to ask his classmate, Nana Shirayuki out on a date. It was good until she called out to him, but he was interrupted by the appearance of his sister Rio. For Akira, Rio is not only his sister but also his first love. Rio used to live alone, but due to a housing situation, she has now returned to her parents house with Akira. When Akira is told by Rio that Shirayuki looks like her, he sees Shirayuki and Rio in her. That night, Akira is seen masturbating by Rio. While Akira is frozen in place, Rio is unfazed and makes fun of the actress he was using as a joke, saying she looks like her. Not only that, but she also grabbed Akira's thing.

Sinful Sis

A sister named Honoka who likes her younger brother Hirokazu, that Honoka sees Hirokazu doing schoolwork with a woman named Akazaki, and she feels jealous. Then he ventured to declare his love and he really wanted a Sex Relationship with Hirokazu. But Akazaki heard a voice from the next room and he suspected Honoka was watching a porn scene. And the next scene is transformed into a sex between Honoka and Akazaki. (Source: Nekopoi and Has Been Translated and Edited)

Oni Chichi 2: REVENGE

Based on the erotic game by Blue Gale. When the school holds a training camp, the father of the Makino family agrees to chaperone his daughters Natsume, Akira, and Fuyu. But training is not on their father's agenda.