Summer vacation had come, with the wealthy college student named Miko Shirogane soothing back with relax that her three months vacation had finally arrived. She had used this opportunity to visit her family's house back in Tokyo, Japan, which was about a thousand kilometers away from her college. Over there awaits a little girl with curly red hair with sparkling eyes. She appears to be Miko's little sister Himeko Shirogane, who always looks up to her with jealousy.
"Hmph!" Himeko grunted, then with sarcasm she said, "I just can't wait until my sister comes here again!"
A sound of an airplane boomed from a couple of yards away as the Shirogane parents walked to the airplane field. Then some bodyguards dressed in black suits walked out the door after the stairs fell down. After the bodyguards lined up, Miko Shirogane, walked down the stairs and between the bodyguards. She was a perfect brunette, and had the same sparkling eyes as Himeko, but purple. Like usual, she wears a gorgeous purple gown. Her parents looked at her with awe.
"Miko, honey! Welcome back!" Mrs. Shirogane walked to her daughter. "Get here, you sweetheart!" Mr. Shirogane followed his wife, ignoring Himeko who just crossed her arms. "How about me?" she muttered.
"Excuse me, Mother and Father." Miko told them. "I need to go to my room and get some privacy." Miko walked straight to her house and into her room that hasn't been occupied for a while.
"Since Miko is in her room," Himeko suggested with a grin marked on her face, "Could you spend some more time with me?"
"Of course we will," Mr. Shirogane replied, "As soon as your mother and I are finished with our work." Himeko's parents left her. Her white Persian cat jumped into her arms, trying to comfort her by puring. "I guess it's only you and me then, Sapphire." Himeko said as she brought Sapphire to her room followed by two maids.
The next day followed on, and Himeko and Miko were sitting on a dining table in a large garden filled with hedges and flowers well treated by their servants. One of the Shirogane maids gave them some shiny white plates in front of them. When the plates were already put in its perfect place, came a booming shout "MAID!!!" from the younger sister. One of the maids came and asked what's wrong.
"You careless maid! You should already know this already!" Himeko boomed once more. "Can't you see that there's still a tiny dirty spot on this supposedly white and shiny plate!?"
Then a spark of white light came towards the Shirogane manor. There was once a black light before, but not white.
"Himeko!" Miko shouted as she knew the light was coming towards her little sister.
"Not now!" Himeko replied. "I'm trying to scold this maid here!"
"HIMEKO!!!" Miko pushed her little sister aside as she worries that it's a white laser from a group of terrorist, or even a radioactive substance that will cause a case of cancer.
But she was wrong.
Her sparkling eyes turned into well-rounded eyes as she yelled "Joyful Bunny!". She started to dance to the music in her mind, she felt violet, powerful, SUPER. The transformation herself reminded her of her alter-ego a few months ago: "Shirogane Z", which is caused by her jealousy of the Powerpuff Girls Z. Now she IS being a Powerpuff Girl Z. After the colorful transformation she had, she ended up with the same outfit as the Powerpuff Girls Z, with a jet black headband on her head and a large frisbee.
Himeko's eyes were wide in amazement, but soon turned into eyes of fiery envy. "You!" Himeko yelled. "You were a sister that I had jealousy on, and now you're a Powerpuff Girl!? You are now on my bl-"
"Wait, Himeko!" Miko inturrupted. "I could use my super-hero status to make you and I become idolized, even more than the other Powerpuff Girls Z!"
Himeko's eyes went back to normal, and grinned has she heard Miko's brilliant idea. "Really?" Himeko asked.
Both of the Shirogane sisters laughed with a distinctive giggle.
The ball on Miko's belt rang, which she held it in front of her. In the screen there was a robotic dog. "Hello, new frie- Shirogane Z!" The dog was surprised that he called someone to replace him, who was now the Professor. "Oh, what a surprise!" The professor answered. "You must be Miko Shirogane, one of the fellows the Powerpuff Girls Z had encountered before. I'm Professor Utonium, the one who's in charge of them. I believe that the white light of Chemical Z was accidentally shot by one of them, so I apologize for that."
Miko replied, "It's OK, Professor Utonium. It has also been a surprise for me, to tell you the truth."
The Professor said again, "You should come to the lab this instance in order to check on you."
Miko grinned, "I'll be on my way." She faced towards Himeko. "I'll be going to the Lab for a while. See ya!" Miko flew with purple light below her, the same light as when she was Shirogane Z.
She went inside the lab and there was the Professor, the robotic dog she met before, a child, and also three teenaged friends she knew their names since they were Himeko's classmates: Momoko, Miyako, and Kaoru. She also had met them before when she was Shirogane Z, though she still doubted her memory.
"Shirogane Z!" The three girls yelled.
"That's the same phrase I yelled as I called her." The robotic dog commented.
"Wait, you were the Powerpuff Girls Z?" Miko asked, pointing at Himeko's three classmates.
"They are." The Professor stated. "But don't tell this to anyone, since they should hide their identity."
"Is that so?" Miko asked elegantly.
"This is also applied to you, Miko, especially if you are a well-known woman." Professor stated again.
"Alright, I swear that I'll not tell as many people as I can." Miko told.
"So it is." The Professor said as he brought Miko to a specific room. "Let's get you checked as soon as possible. Oh I almost forgot, what did you yelled again as you transformed?"
"Bunny," Miko answered. "Joyful Bunny."
From then her superhero named has changed from "Shirogane Z" to "Joyful Bunny".