Cass knew he probably shouldn't be so amused, but still, he was. Even more so he was glad that the friendship between Morag and Percy was as strong as it was. He had his friends after all.
At her questions, he shrugged. 'I have no intentions of hurting Percy, and staying faithful - in spite of my reputation - isn't proving very hard at all,' he said. 'Percy is more interesting than you give him credit for,' he told her with a smirk. 'At least he's more interesting to me, but then he keeps calling me insane for thinking so,' he said.
When she threatened him, he smiled. 'I won't "play him false" as you put it. I know he'd leave me if I did, and to me that would be worse than anything you could possibly do to me.'