Hoshikuzu Witch Meruru

Concept / Plot
This is a magical girl show that only exists in the anime "Ore no Imouto ga Konna ni Kawaii Wake ga Nai". It was broadcast on Thursdays at 5 PM, which puts it at the same timeslot as "Maschera: Lament of a Fallen Beast". During the timeline of the first season of Oreimo, two seasons of the series were broadcast, the second of which was entitled Stardust☆Witch Meruru Double Heart. A third season, entitled Stardust Witch Meruru 3rd Impact, was announced during the second season of Oreimo.

The plot centers on Meru Akahoshi, a grade four, 10-year-old student who magically transforms into Stardust Witch Meruru, whose duty is to defeat the dark witches, led by Thanatos Eros and her Octopus sidekick.

Pretty Star and Evil Star, Comet-kun and Thantos Eros' homeworld respectively, has been in conflict for eons with Earth and Meruru being caught in the conflict. Dark Witches steals human bodies, especially those with innocent heart, as ideal vessels as they possess high levels of dark magic. This very reason is why they threaten to invade the Earth. Thanatos Eros chose baby as her vessel knowing that a baby possesses a pure and innocent soul. Comet-kun made Meruru into a Stardust Witch to counter the Dark Witches threatening to invade the Earth. Meruru was chosen by Comet-kun due to the same reason why dark witches steal human bodies that Meruru posseses an innocent heart.

Meruru's best friend Arufa Kurotsuki, is Alpha Omega, a blue magical girl that seems is the rival of Meruru at first, but her partner later (Meruru launches a kind of purifier attack to Alpha in the opening).

By the third season of Stardust Witch Meruru, Meruru turns against Alpha Omega and an unknown magical girl and transforms into Dark Meruru with the help of someone who resembles Comet-kun, although having a black coat instead of Comet-kun's pink. Dark Meruru then reveals her powers, which include her strongest ability Planet Buster, which unleashes a beam of energy so powerful that it destroyed Earth in a single shot.

First Season

 * Episode 1: Some of Hoshikuzu Witch Meruru merchandise is shown (including a DVD cover).
 * Episode 2: Inside Comic Toranoana, a shop dedicated to fan works called doujin, Kuroneko points out that Stardust Witch Meruru is an outlet for lustful minds doujin-wise.
 * Episode 3: Some of Hoshikuzu Witch Meruru staff is shown (including DVD's).
 * Episode 4: A box of cosmetics contains a set of doujinshi from Hoshikuzu Witch Meruru.
 * Episode 6: Kyousuke's sister is enjoying the Stardust Witch Meruru dakimakura she ordered.
 * Episode 7: Part of the opening of Hoshikuzu Witch Meruru opening is showed.
 * Episode 9: Kuroneko's younger sister watch a few episodes of Hoshikuzu Witch Meruru.
 * Episode 10: Some merchandise of Meruru is shown. The main characters participate in a Meruru Cosplay Contest to win a limited-edition not-for-sale item from Hoshikuzu Witch Meruru as a present for Kirino. Kanako coplays Meruru and sings the Meruru opening theme song.
 * Episode 11: Kirino returns to her usual Stardust Witch Meruru screensaver.
 * Episode 16: Kyousuke, Kirino and Saori watch a Hoshikuzu Witch Meruru movie,

Second Season

 * Episode 1: The trailer for the third season of Stardust Witch Meruru 3rd impact is shown, which features Dark Witch Meruru against her former allies.
 * Episode 4: The trailer for Stardust Witch Meruru Third Impact is once again featured in this episode.
 * Episode 5: There is a Hoshikuzu Witch Meruru event in a Summer Comiket.
 * Episode 6: There is an event of Hoshikuzu Witch Meruru in a Summer Comiket.
 * Episode 10: There is a Meruru Festival. Kanako and Bridget cosplay them. Kyousuke is seen driving into a church using a bicycle decorated with Meruru fan art.
 * Episode 11: Kyousuke ask about a Meruru concert.
 * Episode 13: Some of Hoshikuzu Witch Meruru merchandise is shown.