Cass wasn't so blind to the world that he realised that to most people, Percy seemed to lack humour all together. Personally he couldn't believe how stupid people were to fall for the act though, not when the Percy he knew made him laugh quite often. Like now.
Chuckling, he let his own arm encircling Percy's shoulders as he leaned on him for support. Taking the chance of being so close, he then placed a kiss on his neck. 'Sounds good,' he said, waiting for Percy to take the first step towards the stairs. It wasn't fast, and every step was unsteady, but at least it no longer felt like his insides would break with each step.
That didn't mean he looked forward to the stairs, however. He would much have preferred to be able to rush upstairs quickly so that he could get Percy naked and in bed at once.