I can't explain why I finished this except that I was hoping it would at some point turn into a Rick Riordan novel. (And it was quite quite short.)
It did not.
Maybe I was expecting too much from it, given how much I loved the entirety of the Percy Jackson series, but this was just not a whole lot of fun. It tried to be. It really did. I could tell every time they said something silly or Hades made some overly-modern reference or something unexpectedly ridiculous happened.
It just did not work for me at all. I didn't find it funny, I didn't find it compelling, and I didn't like what they did to the mythology. This wasn't just about making certain characters more or less sympathetic than I have previously read, but several of the mythological figures seemed kind of "out of character" in that they did things I had trouble really rationalizing. It might have been an issue of the characters not being fleshed out enough--I might have understood some of these things better had I known more (and thus cared more) about the characters and their motivations.
It's possibly reading it "out of order" (this is technically the fourth in a series, apparently, though I didn't realize when I picked it up.) caused some of that problem, but I'm not sure I would have enjoyed it much more had I had more background, simply because I felt like the characters that seemed to be introduced in this story were not well-developed either.
I might just have been requiring way too much from the book, but it really grated on my nerves and the love story was kind of awful (I know, Greek myths, but this was quite bad by the end) and I won't be picking up another one in the series to check.