Here is a summary taken from MAL. Will be in spoilers tags because it spoils part of first episode.
One day, however, Kyousuke finds a DVD case of a magical girl anime entitled Hoshikuzu Witch Merle (Stardust Witch Merle), which had fallen into the entranceway of his house. To Kyousuke's surprise, inside the case is a hidden adult video game titled Imouto to Koishiyo! (Love with Little Sister!). Kyousuke attempts to fish out the culprit who dropped the case by bringing up the topic of magical girl anime at the family dinner table. All that comes out is a strong negative reaction from his parents, especially his anti-otaku policeman father.
That night, Kirino bursts into Kyousuke's room and, in perhaps the first conversation she has initiated with him in years, says they "have things to talk about." Kirino brings Kyousuke to her room and shows him an extensive collection of moe anime and lolicon bishoujo games she has been collecting in secret.
Before starting the anime I already was a pretty big fan of the series by reading the little that have been translated of the manga and the novel (10 chs of the manga and 3/4 of the first novel volume). So I already was pretty biased towards liking it. Bias aside I think it was pretty good adaptation wise. I really love Kirino and hope she does well in next year saimo contests, including ours. It also have some other interesting characters that will be introduced later. Also there are many twists to this story yet to happen. Will be lookign forward a lot to every sunday!
So who else is watching this? How you're liking it so far?