In the games
Aliana is one of five Team Flare scientists that are the driving force behind the team, being identified by her orange hair. She is first seen at the Kalos Power Plant with one of the Team Flare Admins.
In the Pokémon Adventures manga
Aliana makes her first appearance in the X & Y chapter alongside her fellow Team Flare members. She and Mable are tasked with taking the Mega Ring, which is currently in X's possession. Upon arriving at X's house, they burn it down and trap X into a corner. Y comes in and tries to save her friend, only for Mable's Houndoom to easily defeat her. Before it can finish Y off, X's Garu saves Y, though she gets badly hurt by Aliana's Pyroar. With Kanga down, Aliana has her Pyroar grab X and begin dragging him away. X's baby Kangaskhan, Li'l Kanga, sees this and reacts to X's Mega Ring, allowing her to Mega Evolve into a Mega Kangaskhan. Li'l Kanga easily defeats Aliana and Mable's Pokémon, forcing them to retreat.