This was very nearly a DNF for me. I really struggled with forming an attachment to any of the characters. I found the main character, Cate, to have too little common-sense and too much trust in complete strangers. I also thought she was waaaay too naive and kind of dumb. I know this was supposed to be a light-hearted, fluffy read, but I just couldn't get behind ANY of Cate's actions. Also, there was absolutely NO emotional payoff in this book. There is a death in this book, and not one of the characters seems too particularly affected by this show of mortality. They're all so strident about it.

Soooo, suppose you've lived as someone's roommate for 2 years. And then they go missing. And out of the blue, some guy starts stalking you, another guy tells you that your roommate is a criminal, and your best friends suddenly start obsessing over another tenant in your building that none of you have ever seen.

When a guy stalks you, DON'T THANK HIM. GET A RESTRAINING ORDER.
When some complete stranger tells you crap about a person you've supposedly known for 2 years, DON'T JUST BE ALL "hm, I'd never have thought it!" GET SOME EVIDENCE, OR KICK THE GUY OUT.
When your friend is consumed with lust for someone she's never met or seen, DO NOT INDULGE HER AND BREAK INTO THE GUY'S APARTMENT. TELL HER TO GET A GRIP.

Ultimately, I didn't find any of this book to be believable. By the 3rd page in, I was ready to throw the book across the room, but I persevered. Only to throw the book across the room when I was done.