There's a moment of stammering before Crowley asks, "Who said you aren't likeable?" in a way that's almost defensive of her. In fact, the demon looks ready to jump out of his seat and give whoever it is a good slap.

But he gets it. It's why he wears the glasses. Not because his eyes look different, but because with them on, no one can see that he's frightened or nervous, no one can read where his mind is at or hurt him. It's an impenetrable mask... and the only person he'd taken them off for before Alice was Aziraphale... who knew the real him.