[Ladies and gentlemen, Ciel has inadvertently discovered the cure for demon depression. Or dourness, either works. He's so proud of his accomplishment that he'll just deadpan at you. It'll go hand in hand with the moment of silence for Sebastian's dignity.
In fact, he has so much respect for Sebastian's dignity that he pushes Sebastian a little further away from him by digging two fingers into his forehead, because ew germs and who in their right mind would move themselves away when they can push someone else instead? Oh, I'm sorry, did it look like Ciel was going for a caring, temperature check instead?]
You're ridiculous. [Because clearly, that's the snappiest of snappy comebacks that he can deliver right now.] The next time you complain about me being under the weather, I will bring this up in extensive detail. You think suggesting I do manual labor is a funny joke? Are you the Undertaker now?