High schooler Kyousuke Kousaka discovers that his cold, popular younger sister Kirino is a secret otaku with a hidden collection of anime and younger-sister-themed eroge, and becomes her reluctant confidant against their strict father. These three special episodes close out the second season's run, extending the Oreimo 2 adaptation past its televised finale rather than serving as an entry point. They continue the Kousaka siblings' story from where the season left off.