Ilona is an apprentice of the Wizards' Tower who was originally from Lumbridge. She was kidnapped by Caitlin, formerly a fellow apprentice who had turned to Zamorak, along with two other Zamorakians, Reese and Kayle. They intended to use her to fulfil The Blood Pact and gain access to the secrets of the powerful necromancer Dragith Nurn.
She was saved by the combined efforts of an adventurer and Xenia, a more seasoned adventurer. She returned to the Wizards' Tower afterwards studying on the tactics to stop herself from being defenceless ever again. Her speciality depends upon the choices made by the adventurer while rescuing her. If Kayle or Caitlin were spared, she studies stun and bind spells in order to incapacitate without killing. If they were killed instead, she studies elemental magic to stop attackers dead in their tracks.
Ozan, one of the Signature Heroes, will sometimes say he was out on a date with Ilona and how she kept changing the subject back to the adventurer who saved her instead of him.