Is this cat okay? Do you need us to call someone, cat?
Be real: if your friend was acting like this at a party, you'd be worried. It's either drugs, or they're dead and someone discreetly put a pair of sunglasses on them so it doesn't spoil the vibe.
Since this is a kitty-kat who is famous for sitting in a chair, hopefully this is just an attempt to "re-brand" as a cooler cat that sits in a chair. At least you can pretend this cat is listening to you when you talk to it. That's why most people wear sunglasses in the first place: so they can nod off while their friends talk about themselves.