Lucien has never felt anything like this before. He's still mad at Wrath for the way she treats his sister though he also understands how her nature forces her to be that way.
But to punish her, he can't just beat her or even make her mad, as that's like pleasing her. So he thinks about messing up with her all the ways he can.
Of course, the first option that he thinks is messing with her feminine feelings. He has been teasing her with subtle stimulations since they started fighting, still releasing some of his anger on her in a mix of emotions.
But as soon as he saw her smile at him after he exploded her body, he realized how crazy she really is. And all the negative feelings he had for her became even less insignificant.
And new feelings rose in Lucien's heart. He still wants to mess up with her, but he also wants to take her to him and take care of her like he takes care of all his wives.