Orias is the 59th spirit of the Ars Goetia, he is a great Marquis and appears in the form of a lion that holds two great serpents in his right hand with a snake's tail riding a mighty horse. His office is to teach the virtues of the stars and know the mansions of the planets. He also transforms men and gives dignities, places, confirmations, and the favor of friends and foes. He governs 30 legions of spirits.
"Origin: Israel. The Great Marquis of Hell. He commands 30 legions of demons. He has a lion's face, holds two snakes, and rides a giant horse with a snake's tail. He can change forms, bestow authority, and teaches medicine and astrology. He also has the power to make angry people reconcile with one another."
—Shin Megami Tensei A-Mode DDS dictionary
Orias serves as the first boss. He appears as a doctor conducting strange experiments on his patients in an effort to create slave super-soldiers, but is defeated before he could experiment on the protagonist.
"One of the 72 demons of the Goetia. He rides a horse and has the head of a lion and the tail of a snake, with vipers held in both hands as well. He is knowledgeable in astrology, can transform a human into any form, has the power to turn foe into a friend, and can give people new titles."
—Shin Megami Tensei: Strange Journey compendium
Orias first appears in Sector Antlia as the first boss in the game. He first appears as the strike team blasts through the boulder blocking their path to reach the Blue Jet, coming up behind them and either killing or severely wounding some of the strike team members. Slightly later, he appears in the Blue Jet's crash site and threatens the crew. Commander Gore very nearly defeats the demon, who feigns a retreat, but when Gore lowers his guard, Orias sneaks behind and kills him. The protagonist proceeds to fight Orias and defeats him.
Orias later appears as a standard enemy in Sector Delphinus. While the Orias in Antlia appears to be simple minded, the standard Orias in Delphinus is actually quite intelligent and quite capable of conversing with the protagonist.