Raven, also known as Schwann Oltorain, is an Imperial Captain slash Guild member. Not much is known about his early life, but it is explained that many years before the game starts he was a soldier in The Great War between the human race and the Entelexeia. During the battle, Schwann died but was revived due to a man named Alexei replacing his head heart with a Blastia that enabled him to continue living. Due to this, however, Schwann owed his life to Alexei and was forced to do whatever the man bid him to do, leading him down many dangerous trails.
Raven is first seen in a jail; a place which he calls relaxing, somewhere he can think. He is collected by Commandant Alexei, which confuses the protagonist, Yuri, until he notices that Raven dropped him a key to escape. From this point on, "Raven" is not seen until he arrives in the Port Town Nor, leading the group into a tricky situation by forcing them to use a lift that lead into the Magistrates basement rather than his home. The main group meet the character again, however, although this time they see him as "Captain Schwann": Schwann's Brigade capture the group and takes them to Heliord. In Heliord, the group are pardoned by Alexei and, as they are leaving, the camera cuts to a scene of Alexei telling Schwann that he has a mission for him.
"Raven" then meets the group in the great forest they are examining due to its Aer properties, and eventually joins the group. It's revealed that he is a high-ranking member of Altosk, one of the five master guilds, and is incredibly close to its leader, Don Whitehorse. Despite complaining of his age frequently and how the "young ones" treat him badly, Raven is apt in battle using a bow that can transform into a knife when he is close to an enemy. Raven does, however, leave the party and return at times, eventually sticking with the group when they travel to the great city of Nordopolica. Instructed by the Don to deliver a message to the Duce, Belius, he joins the group in their travels.
Raven's secret identity is hinted at when, during their return from the Deserts due to their inability to meet Belius, Yuri's old rivals who are, incidentally, members of the Schwann Brigade, block their path. Raven cries "attention" and the men, recognising their Captain's voice, stand to attention and the group are able to evade them. Raven is then able to deliver his letter to Belius, but events that concern the Don's grandson result in her death. The group return to the Guild Capital, Dahngrest, and the Don is forced to give his life in payment. Raven agrees to join the party and they continue their quest.
When they arrive at the Krityan city of Myorzo, they meet with the Elder. During the meeting, however, Estelle and Raven disappear and one of the old portals that lead to the mainland has been activated. Although they don't wish to, the group assumes the worst and they realise what must have happened: Raven has kidnapped the Princess Estelle and has taken her to Alexei at the evil Commandant’s orders. Upon trying to look for Raven and Estelle, the party find that Estelle was captured by Alexei, and the party goes into Baction, a temple made to worship an Entelexeia, to try and get her back.
When they confront Alexei in the basement of the shrine, Alexei is able to escape due to the interference of the Schwann Brigade. Eventually, Captain Schwann emerges and dismisses his men and the group realise that he is Raven from his voice and their dog, Repede, recognising his scent. A battle ensues and Schwann is sure that he is going to die. During the fight, the front of Schwann's clothing rips apart, revealing a pink Blastia on his chest. The Blastia is fluctuating, however, and Schwann is still certain that his death is imminent. The group also finds out that Schwann didn't stay behind to kill them, just to stall them, as the entire Baction temple began to collapse. The party manages to convince Schwann to help them, who proceeded to blast a hole in the wall and hold the ceiling up as the party escapes.
The group mourn the loss of their friend, but are forced to continue their journey in order to find Estelle. When they reach the entrance to the Shrine, they meet three of the repetitive members of the Schwann Brigade; LeBlanc, Adecor and Boccos. When the trio find out that their Captain is dead their despair, but informs the group that Alexei has gone to the large Imperial Battle Station, the Heracles. The group head there.
When they land upon the station, out of nowhere a voice appears; it seems that, despite their fears, Schwann did not die in the Shine after all. After punishing him for his actions (each member of the group hitting him) he is told that his life belongs to them now. Raven accepts his fate, saying that his other-self, Schwann Oltorain, died in Baction and he can happily be Raven now. By becoming "Raven", he is free to do as he wishes - which is following the party. It is never revealed how he survived the ceiling collapsing, though it assumed that it was due to the power of his Blastia heart.
Raven continues to follow the group in their mission to, first, defeat Alexei and then to overcome the greater evil, the Adephagos. When the game ends and all the Blastia are converted into souls Raven still lives; despite having a Blastia as his heart, it is powered by his own life force, not a core. During a side-quest in the game, it is revealed that during the Great War Raven had fallen in love with a Knight named Casey, a woman who inspired him to take up the use of a transform-bow and died in the Great War. Unfortunately, the woman loved a Knight who is explained to be Yeager, a nemesis of the group. After the group fight Yeager's henchmen they hand over Casey's bow as a gift to Raven, who treasures the item.