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The Di Gi Charat Summer Special was a four episode series that aired over two days, August 22, 2000 to August 23, 2000. This was the first series that Piyoko appeared in and the plot involves her attempting to hold Dejiko hostage for ransom. • Summer Special 2000 Episode 1 - Here comes Pyoko-nyo! • Summer Special 2000 Episode 2 - It's the Black Gamers-nyo • Summer Special 2000 Episode 3 - The Return of Abarenbou • Summer Special 2000 Episode 4 - Summer Bug (Source: AniDB & Wikipedia)

Based on Ekaterina Kurae's chapter 16 from the manga, and episode 10.5 of the anime.

ONA Special episode #11.5.

Three monsters, Bem, who looks like a gangster, Bero, who looks like a boy, and Bera, a witch, act as agents of justice, hoping that they will be allowed to become human. Several episodes involve them protecting a young boy. The style of animation is fairly distinctive, and the storylines not without interest. (Source: AniDB)