Give in.

Robb felt his mother twist in his hands, and he worried briefly that he had offended her. But then he felt her loosening his breeches, and he knew that the moment had come. Pulling away from her kiss, he worked to loosen her dress.

"Ohhhh, Robb," whimpered Catelyn . "Do you want to see your mother's titties?" Robb nodded he stepped out of his pants. "So that's why you were watching me in the bath?" said Catelyn with a smile. Robb looked at her in surprise. "Oh, I knew. I knew you were watching. Watching and playing with yourself. It made playing with myself so much... hotter..." She gave an angry groan as Robb tugged at her dress. "Oh, tear it off, tear it to pieces, anything to get it off!"

With a loud rip, Robb sent the pieces of his mother's dress to the floor, drinking her naked beauty. As Catelyn smiled at him, the Lord of Winterfell leaned forward and took her nipple in his mouth, while one hand went to the juncture of her thighs. His mother was already dripping wet down there, Robb realized. Just as he was certain she was realizing that he was hard and ready, as her delicate hand engulfed his member.