First, the game is MASSIVE.  You'll sink a ton of hours into finishing it.

Ok, everything else, now:

• the gameplay is mostly clicking through text, so it could get really tedious, but it's also a good one to set to Auto, and watch it like a movie
• it started as a slice-of-life game, but then added mystery and crime drama, and then sci fi, and then fantasy.  there's a lot going on.
• I find the art a little lacking, in general, but
  • the faces are good; I like that they have a bit of Final Fantasy in them, which helps a bit with the uncanny valley, and the expressions are good
  • the figures can be a little stiff
  • and the women's breasts don't sit naturally; it's like the women all have bad implants, or they're all plastic dolls.  for an erotic novel, I need to see more realistic breasts; ironically, it's the anime art styles that usually do the best job at it.