Ore no Imōto ga Konna ni Kawaii Wake ga Nai
Volume 13: Ayase If Route

Ayase route is being adapted. The light novel that matches with a certain route from the game. The Ayase Route is where instead of choosing his little sister Kirino, the main character, Kyousuke, chooses to be with her friend instead, with interesting consequences. Stay tuned for more updates. The next volume is Volume 13.