In this post I saw you can romance Diana Allers.
How can you do it? I have done some missions but can't speak with her, and there aren't any options besides getting her out of the Normandy.
After each third of the game - Priority Tuchanka, Rannoch, or Thessia, Diana Allers (if aboard) will send an email requesting an interview. Shep can go up to his cabin and use the intercom to send her up for an interview.
After she asks her questions, she'll turn off the camera and make some small talk - after the first interview, you are given the option to flirt with her or turn her down. If you turn her down, she never mentions it again, but if you flirt with her, you can then flirt after the other two interviews and eventually she will become a love interest.