Himeko Shirogane also know to her alter-ego form Princess, is a main antagonist in the series. She is a wealthy student of the middle school in Tokyo City. She was one of the many victims who had been hit by the black aura and can transform into Princess by Sapphire's scream. But in a similar way as Sakurako Kintoki transformation, the Black aura effected on her isn't permanent.

She is originated from the show the Powerpuff Girls and been adopted by Toei Animation. The original creators of the characters and the show is Craig McCracken.

Himeko goes to the same school as the Powerpuffs and was struck by a black light, which caused her appearance to change, with the exception of her outfit. Her powers are used based on her desires to be recognized by people. Once she is back to normal however, she does not recall any events that occured while she was evil.

It's shown that she has a strong dislike for Momoko, Miyako, and Karou, and often tries to get them into trouble even when she is not evil. She becomes somewhat friendlier towards them as the series progresses. In one episode, the Powerpuff Girls Z found out that Himeko has a big sister named Miko who does everything better than her, and even draws attention by their parents. Unlike the original cartoon series, both of her parents' faces are shown and her mother is alive and around. She has a cat named Sapphire, whose scream causes Himeko's transformation.


Like her original counterpart from the American cartoon, Himeko is often spoiled and nasty towards others. She taunts people who she calls having a " lower class ", with a very arrogant and bad-graceful manner. However, unlike her counterpart, she's less psychotic and doesn't throw as many tantrums for not getting what she wants. She is also capable of showing kinder emotions, such as her love for her cat Sapphire and sister Miko, or when she is genuinely concerned about Blossom's feelings, so she has a few redeeming qualities.

Himeko is often shown to enjoy being the center of attention at school and becomes jealous if someone is taking it away from her. From a different perspective, Himeko is avoided by her parents a lot, because of being the younger child of the family. She's ambitious because of it, and would use force to take whatever she wants by herself, without her fathers help, as shown in the original. She has two friends, whom she calls her "entourage", who follow her around, complimenting and flattering her.