|Previous Affiliation||Aizen's Army|
|Previous Occupation||Novena Espada|
|Base of Operations||Las Noches|
Aaroniero was present at the Espada meeting when Ben Tennyson entered Las Noches. When the hero was brought to Aizen's throne room, Aaroniero voiced his surprise that a "mere boy" could infiltrate Las Noches. Like his comrades, Aaroniero was surprised by Ben's shape-shifting powers. After Aizen convinced Ben to join his cause, Aaroniero introduced himself to Ben.
Invasion of Las NochesEdit
Battle with Rukia KuchikiEdit
Las Noches was invaded by Ichigo Kurosaki and his friends in an attempt to rescue the recently abducted Orihime Inoue. The group split up, and Shinigami Rukia Kuchiki wandered into Aaroniero's headquarters, where they battled after a rather confusing introduction.
Aaroniero was ultimately slain by Rukia. With the last of his strength, he telepathically sent an image of his fate to his comrades. Tia Harribel and her Fraccion made note of this. Despite not liking Aaroniero, Ben felt some amount of grief at Aaroniero's death, though this changed slightly when Nelliel Tu Odelschwanck revealed Aaroniero's power to gain the abilities of other beings (namely Hollows) by eating them, causing Ben to realize that Aaroniero would have tried to eat him if he could.
- Aaroniero was the first Espada to die (not counting Luppi Antenor, who was a replacement Espada).