[It's quite possible that he's thinking very intensely about how, after he's finished with the floors, he'll take a five minutes break and go visit his kitten (that definitely isn't living in his hotel room. that he definitely hasn't adopted. that he's certainly not hiding from Ciel) and then all this frustration will disappear for a little while and everything will be perfect.]
I suppose it would make sense that is something that would remain consistent across worlds. [Since, indeed, even when contracted demons are hardly big on working together with others...] Perhaps were any of them to come here, they too would gain more experience with it. I cannot say I know anything about your universe, of course.
[Here's where she tells him what demons in her world are like! Or what her relationship to them is - that works too.]