Well, Damien often worries over whether he's being tempted by the promise of Gerald's power for his quest.

Oh! And once, he notices he's starting to go grey and admits to himself the only reason he's not being vain about it is because it's the sort of thing Gerald would do. He didn't quite muse over the awesomeness of unaging immortality, but the implication may've been ever-so-faintly there?

I am getting so far ahead of myself...