Pokémon: The Electric Tale of Pikachu is an official Pokemon manga series created by Ono Toshihiro. Loosely based on the anime, with significant characterization deviations. It is probably best known for giving Misty a skimpier outfit (a black highleg slingshot swimsuit that was later censored as a wetsuit in English versions) and significantly larger breasts.
Japanese title: Dengeki! Pikachu