Annona's origin is unknown, but what is certain is that she as an Isu were the humans superior. After the events of the Unification War, Annona and Diana – another Isu – were stationed in the outskirts of Feyan, whereas they made sure the humans executed their farming duties. In order to make them obey, Annona and Diana used an Apple.
Annona had a love–hate-relationship with the scientist Minerva. Whilst the latter viewed the humans as inspirational and passionate beings that could learn the First Civilization about love, art and music, Annona thought of them as mere tools. They were destined to become their servants – which was their purpose, the meaning of their creation. However, Annona admired Minerva for having such faith in the humans – and that she could see all the good in them. Minerva thought good of Annona because of her calculated mind and influence on the humans, even when not using an Apple.
Annona died giving birth to Pluto.