You say 'the Manga' but what I'm seeing is that there are five simultaneous manga, four of which are just straightforward retellings of the same story in different styles - either more comedic or more dramatic or whatever.
So in addition to that version, there is also:It looks like the series is closer to the second out of those three, which is the more 'serious' take on the concept, I guess. That one doesn't have the joke about accounting. So it's not purely an issue with the anime adaptation.
So in addition to that version, there is also: