Rex reached out his hand and undressed her lower part.
Mainly, he was taking off the armor on her right leg and also the stocking she wore underneath it.
"What are you doing? Is this what you're aiming for all along, you perverted barbarian?!" Mira shouted.
She was horrified at the sight of Rex taking off her leg armor.
"Don't overestimate yourself," Rex sneered in response. "You're not that pretty that I would go to this length to assault you. To finish the transformation, I need to put my pack mark on you. I can't really put it out in the open, now, can I?"
Though her house wasn't as respectable as the Aurelius House, Mira is still a noblewoman.
She must have several personal maids who would help in her daily activities, and all of them must've known her skin, like it was the back of their hands. If Rex put the Silverstar Mark on an open place, like her arms or neck, everyone would notice, and it would raise questions.