"Her bold features were just feminine enough for beauty, but too masculine for anonymity."
edited to include the comment of Feed the Swarm (just in case he decides to leave BL, in which case his comment would disappear and then I would be sad. -- because he nailed it.):
Come on, it's not that bad. ^_^
The author is saying that she's beautiful, but not generically so. She's striking.
Think of Ripley or Vasquez from Aliens. Beautiful/sexy, but also a bit odd-looking and masculine, impossible to forget. Too unique to be just another hollywood face.
Compare that to the blandly gorgeous kick-ass females in the current crop of x-men films. Nobody is going to be talking about that utterly forgettable girl from Transformers in 20 years from now, the way that Ripley and Vasquez are truly iconic, and will remain so for another 20 years.