Xadhoom is a mutated alien. Before the mutation she was the most brilliant scientist of her planet. Her physiology is an unknown synthesis of solid matter and pure energy, the energy levels are comparable to a super-nova.
She started out as an enemy of Paperinik, but they soon joined forces in order to destroy the Evroniani.
This association continued until she eventually sacrificed her life to ignite a sun for the new Xerbian homeworld.