The son of Lissa and the cousin of Lucina from the future. His supports and conversations with Laurent during the Hot-Spring Scramble reveal that he is a bit of a writer, and always tries to write other characters into his stories the way he sees fit. He is quite proud of his heroic lineage and bears the Mark of the Exalt on his arm, proving that he and Lissa are of Ylissean Royalty bloodline. Owain has an "uncontrollable sword hand" which apparently seeks battle. However, this is revealed to be merely for dramatic effect, and he admits in the Hot-Spring Scramble that he actually does not have uncontrollable power. He is part of the Justice Cabal along with Cynthia and Morgan.

Owain in the future helped his parents fight off the Risen once he was old enough to fight. However during a battle, a Risen archer attempted to attack Owain from behind, but his father pushed him out of the way and died taking the arrow intended for Owain. Later, during another battle, Lissa was killed while she was healing the wounded. Owain was given his mother's ring, which he continues to wear. In an Event Tile conversation with Lissa, he also took a piece of the staff she used when she was killed and named it "Lissa." He joined Lucina and the other children to return to the past and prevent the ruinous future.