Don't worry, everyone. Kaathe is only going to be this mushy in the dreams (and maybe if he, Cythlla, and Henry are alone). Back in the Waking world, he'll be his normal, pessimistic self again! Although, he can be counted on to help Henry protect Cythlla. 

And if Marcus tries anything and gets away with it, it's okay. It doesn't matter in the end. After all, death is inevitable. Who cares if they find half his body frozen, and the other half mauled by some sort of demon while Kaathe is being controlled by said demon?