Luca looked at Irene who had already lost her consciousness coldly. He only wanted to provoke her a bit and make her realize her place. He wanted to make her aware that he didn't like her meddling too much on the military affair. but in the end, he got emotional and used some of his power to weaken her. Lately he couldn't control his own emotions regarding Ayana. He felt like something inside of him was burning when he heard someone mention Ayana in a degrading way.
He hated it when Irene talked like being born as a human was something humiliating. She talked like she has or was the power to force him to marry Ayana. That was what Luca wanted them to think. He wanted Irene to feel that she had power over him. when in fact there is no power in this world that can prevent him from marrying Ayana. She is his and no one could change that.