Deon Aarlaa was a Twi'lek of the male variety. Employed by Clan Ryo, he functioned as a personal guard for Baron Volnos Ryo, who was the leader of the Ryo Syndicate and the sibling of Je'daii Ranger Hawk Ryo. Circa 25,793 BBY, Aarlaa assisted Clan Ryo in the abduction of Oma Dessain, who was the youngest daughter of Eomin Dessain, the head of Dessain Mining. Hawk Ryo was dispatched to locate the abducted girl and avert conflict between Dessain Mining and its workforce. He uncovered and assaulted the kidnappers' base in the settlement of Kainnan. During this confrontation, the ranger employed the dark side of the Force to Force pull Aarlaa in his direction, ultimately running him through with his sword before an alarm could be raised.
The initial appearance of Deon Aarlaa was in the short story titled Eruption. This story served as a prequel to Dawn of the Jedi: Into the Void, and was authored by John Ostrander. It was published in Star Wars Insider 141.