Season 0 of Oreimo premiered on February 22, 2011.

The true end arc of Ore no Imouto. These four episodes branch out after the 11th episode of the main TV series and present an alternative version to the end of the TV series. These episodes contrast with the good end arc of the TV series, which was an original ending written for the anime, and instead closely follows the original story from the light novels.

Season 1 of Oreimo premiered on October 3, 2010.

Living in the shadow of his talented younger sister, Kyousuke Kosaka conducts a normal lifestyle until he accidentally finds out that she hides a secret. In addition to being smart, pretty, and popular; Kirino Kosaka is also an obsessive consumer of anime and eroge (adult computer games). What will Kyousuke do? Will this tear their already rocky relationship apart or bring them closer together?

Season 2 of Oreimo premiered on April 7, 2013.

Kyousuke brings Kirino home from America where she attended a special track & field camp. Surrounded by her friends, Kirino gradually gets her life back to normal. In stark contrast to her friends is Kyousuke, who is unhappy with Kirino's attitude towards him. She has been ignoring him since she came home, as if their relationship had gone back to how it had been a year earlier.