Oreimo

Kousaka Kyousuke, a normal 17-year-old high school student living in Chiba, has not gotten along with his younger sister Kirino in years. For longer than he can remember, Kirino has ignored his comings and goings and looked at him with spurning eyes. It seemed as if the relationship between Kyousuke and his sister, now fourteen, would continue this way forever. One day however, Kyousuke finds a DVD case of a magical girl anime which had fallen in his house's entrance way. (Source: Crunchyroll)

NAKAIMO - My Little Sister Is Among Them!

Is insanity hereditary? Shougo Mikadono's beginning to think so, because the terms of his late father's will seem crazy and following them may drive Shougo bonkers as well. Oh, it sounds simple at first: before Shougo can claim his VERY large inheritance, he just has to start attending a certain new school and find a nice girl to marry. It's a little unromantic, but perfectly do-able, right? After all, all the girls seem quite friendly, so all Shougo has to do is find one he has something in common with. EXCEPT, and here's the kicker, it turns out that Shougo has WAY too much in common with one of them, because she's actually his long lost sister! And he has no idea which one she is! Will Shougo meet and court his Miss Right without committing something very morally wrong? Can he find his future bride without slipping into the wrong set of genes? And if his little sister does reveal herself, just how much will be revealed and under what circumstances? (Source: Sentai Filmworks)

kiss×sis (TV)

Keita has two older step-sisters, Ako and Riko, but since they aren't related by blood, they love him in a lustful way. After a mishap at school, Ako and Riko finally confess their love to him. Keita dislikes the thought of seeing them other then brother and sister, but as he tries to enter the same school as his sisters, he slowly becomes attracted to them. (Source: Anime News Network) Note: The first episode was aired as an online preview on Bandai Channel between 25th and 26th of March 2010. The regular broadcast started on April 5. </i>

The Hill Dyed Rose Madder

On his way to school Junichi Nagase saves a girl from danger. Later due to a misunderstanding he kissed her. Shocked and disgusted, and without understanding what just happened or why, she screams at him and tells him to "just die!" As it turns out, the girl, Yuuhi Katagiri, is a new transfer student and, much to the surprise of Junichi and his younger sister Minato, their father arranged for Yuuhi to be Junichi's future wife! Of course, getting married to "that perverted idiot" is the absolute last thing Yuuhi wants! Junichi's crazy school life with his tsundere bride-apparent has begun! (Source: Animesuki, edited)

Kiss x Sis

Keita is studying hard for a high school entrance test, but his two beautiful elder twin stepsisters are a constant distraction. Though they mean well, Ako and Riko are also extremely sexually assertive and interested in Keita. At first, he fends them off, but little by little, with each kiss, Keita becomes close to both twins until a forbidden love triangle develops. Will taboo-breaking love bloom between two of them... or will Keita at least get into high school?! (Source: Discotek Media)

Yosuga no Sora: In Solitude Where We are Least Alone

Haruka Kasugano and his twin sister Sora have lost both their parents in an accident, and with them all their support. They decide to move out of the city to the rural town where they once spent summers with their late grandfather. At first everything seems familiar and peaceful, but changes come as Haruka starts to remember things from his youth. (Source: Anime News Network)