Shion is a French friend of Momoka Nishizawa, both coming from wealthy and noble families. Pierre serves as her trusted butler, much like Paul does for Momoka. After her parents passed away, she inherited the dragon book, which only she could read; the words appeared in her mind when she looked at it. She was able to hear the Earth Dragon's voice and summoned its tails to spread across the world.
She invited Momoka and Tamama to her home in France. During their stay, she began transforming the rest of the Keroro Platoon into dragon warriors. She successfully transformed all of them until Keroro and the Hinatas arrived to help Momoka, thwarting her attempt to transform Keroro.
She then traveled with the Hinatas and Keroro to destroy the Earth Dragon's egg. Along the way, she transformed Keroro to assist his friends. When the Earth Dragon was summoned and threatened to destroy the Earth, Shion appeared to sacrifice herself, but ultimately, she and the Platoon members were safe and returned to their original forms.
She appeared holding a glowing blue egg, which soon hatched into Terara, the Keronian form of the Earth Dragon. Shion later attended school with Terara, who wore her hat, and occasionally received visits from the other Keronians and their partners.
(Source: Keroro.wikia)
