When Asura’s wife was murdered, her brother, Yasha, blamed Asura for her death and turned against him. Yasha will be a playable character in Asura’s Wrath. We aren’t sure just how he’ll fit into the story, but Capcom say he’ll have to decide whether he’s with Asura or against him.
Whether or not this choice will be up to the player is unclear at the moment as well. We’ll keep an eye out for more details at the Tokyo Game Show. In the meantime, here are screenshots of Yasha: