He is very needy! He wants to kiss his girlfriend and be kissed in return, let him live! It doesn't mean he isn't content to wait while Jyn lavishes attention on the dog for a little while, because it'll be better in the long run. Chantico would never stop demanding it.

"She is not going to eat your shoes, Jyn." He can tell she is pausing to watch, but the dog won't move away until Jyn does. He pats the spot beside him on the couch. Please come over and let him snuggle you. "No, I have just confirmed it with Shara for sure. There is no one to watch Chantico, and I cannot bring her this time. Not that I can really bring myself either. Besides, I would feel too awkward having Christmas with Kes's family."

They're perfectly nice people, he's sure, but Cassian hasn't met them yet, and he doesn't want to do that over such a big holiday. He doesn't blame his sister for spending time with the Damerons this year; it isn't like they have anyone to go to themselves. It'll be a nice good first Christmas for Poe, even if Cassian is trying not to let himself be upset over missing it. "I promise I will not spend it alone, Baze and Chirrut have already told me I am coming over."

Not invited. Told him.