...since everyone else has already commented on Hades, Cloud, and Sephiroth, I just want to say that
//"Since Mr. Scrooge was kind enough to help me understand the financial and legal aspects of employment--" and here she pulled a thick sheaf of legal papers out of her schoolbag -- "we analyzed the numbers together//
is possibly the most terrifying sentence fragment ever in the most awesome way. ^_^
(I expect she was steered in his direction by his grandnephews, who other than Aerith are likely to be the only ones with any clue as to how to work with and around someone like Tohru without losing oneself.)
And given the side-effects you mentioned in an earlier comment, I imagine Tohru is now one of Donald's favorite people (at least, until she starts thinking that Mr. Donald would probably be so much happier if he didn't react so irritatedly to such minor things....)