The Battle of Kins troubled Artemis even though he never fully admitted to it. The fact that his half brother, the true heir to his throne was fighting a war ignited something inside him. Could he turn back to him after he's done with Prophis? Did Aprophil know his own true nature?
Ever since Artemis learned about Aprophil when he visited Lord Dundrey in his tavern, he never spoke about it with Aurora. He thought she didn't know about his half brother, or anything regarding Aprophil and he wanted to keep it that way.