Excella Gionne is a British-Italian businesswoman who oversees TRICELL's Bio-Weapons program while leader of the conglomerate's African branch, establishing a massive bio-weapons research facility in the Kijuju Autonomous Zone within a former Umbrella facility while regrouping a bio weapons dealer named Ricardo Irving to provide her with funding for the Uroboros Project she developed with Alex Wesker.
However, despite her love and loyalty to Wesker, he infects her with the Uroboros in an act of betrayal with her body unable to stabilize the virus as she mutates into Uroboros Aheri while absorbing a pile of corpses to increase in size before Chris Redfield and Sheva Alomar manage to kill the creature.