Crescenta Cosma, also known as Crescenta the Eager, is the 31st Queen of the Kingdom of Fairy World, a daughter of Festivia Cosma, the younger sister of Dirhhennia Cosma, and Timmy's fourth great-godgrandmother. She is first mentioned in Timmy's Guide to Mastering Every Planet, and her history is expanded upon in The Fairly OddParents!: The Magic Book of Spells.
Like her mother Festivia and in stark contrast to her older sister Dirhhennia, Crescenta is very cheerful and optimistic, having a great passion for helping others and a strong moral compass. She is an incredibly hard worker, doing as much as she can for Fairy World even before being crowned as Queen. However, she can be somewhat of an authoritarian and schemer in her enforcement of rules and order, imprisoning any who do not follow the rules she puts into effect and rigging elections to get the result she desires.
Crescenta is also very complacent and obnoxious, always believing that she is more superior than her older sister. As an example, she thinks that she has "rescued" the Millhorse Chastity after she received her wand from her. Another instance is how she describes herself as the "Levitato Master".
- Note: The following information is from The Fairly OddParents: The Magic Book of Spells.
Crescenta inherited the Royal Magic Wand from her mother Festivia, superseding her older sister Dirhhennia after she was deemed unfit to rule Fairy World. Immediately after receiving the wand, Crescenta set about improving Fairy World and the lives of its people, such as establishing the Future Leaders of Fairy World club with other princes and princesses, joining the Junior Castle Guard to watch over Cosma Castle, and doing a lot of volunteer work for the peasants.
Crescenta was crowned Queen of Fairy World at age 20, ten years after inheriting the Royal Magic Wand. One of her largest and most ambitious undertakings as Queen was establishing a form of government within the monster population, overseen by the Cosma family. With the help of her goddaughter Emily Kelpbottom, Crescenta organized an election to crown a monster king and queen, resulting in the coronation of King Sudo and Queen Pemma Avarius.
Crescenta would continue to rule Fairy World with Emily as her chief advisor before passing the Royal Magic Wand on to her daughter Rhina.
In "The Past and the Furious" and "Ghost of Butterfly Castle", Crescenta is depicted in tapestry in the Butterfly Castle's "Grandma Room". In "The Tavern at the End of the Multiverse", she appears as a voiceless ghost inside Glossaryck's eye. In "Cleaved", she appears as a ghost again in the Realm of Magic as Timmy, Cosmo, Wanda, and Eclipsa destroy the magic.