I dropped princess nine after reviewing the plot and watching the ending. The story was filled with cliche characters, yet was fairly enjoyable from what I had watched. There was a hint of romance, but it was actually not the absolute best sub-plot there was. In fact, it really disappointed.
On a good note, it was very VERY interesting and could be sweet at times. There were many plot twists that related to a true story. I would say that the ending could have been better, and the plot could be more solid. Other than that, it's a nice anime just to watch for fun.