Aria was born the daughter of Luce, and inherited leadership of the Arcobaleno and the Giglio Nero from her. Little else is known of Aria's past; however, she was shown to be kind and was loved by her subordinates and Uni. She was very much aware of the Sky Arcobaleno curse and, in that future, she knew that she was going to die soon because of it, and cried. Gamma visited her before his mission, bedridden, as she told him that it would be the last time they could talk like this, angering Gamma who told her that she just needed more rest. Unfortunately, when Gamma returned after his mission, Aria had already passed away.
Aria was the one to administer the Sky Trial in the place of her deceased mother, her Trial involved Tsuna having to do everything she said to do without a complaint. Even though it wasn't part of the Trial, Tsuna even went as far as protecting her from men possessing Box Weapons without knowing if she herself was an enemy. In the end, Tsuna obtained the Sky seal after completing the Trial of Tolerance.
Hidden from the other Arcobalenos and Tsuna's Family, she watched Reborn's Trial.
Aria is mentioned to have known that the future Uni had come to the past, sending her Sky Pacifier to Uni to allow her to fully fulfill her role as the Sky Arcobaleno.
Aria appears in a flashback of Uni's while the latter is sacrificing herself to revive the Arcobalenos. In the flashback, Aria states to Uni that she should smile from her heart when she is happy.
Aria is briefly seen in Gamma's imagination when he recalls Aria's disappearance when they received the memories of Uni and himself sacrificing themselves, also mentally commenting that he's already accepted the fact that she was dead, leading Aria's life status to be in question. However, later Uni revealed that Aria is dead when she told Gamma that he is still unable to forget about her.