This series has been on my TBR list for a while now and I figured with the series actually being complete I should get to it. 
 I should start out by saying that I absolutely love the alternate Victorian London world that Gail Carriger has created. One where there are vampires, werewolves, ghosts, and preternaturals which is what our main character Alexia Tarabotti happens to be. 
 The title Soulless references Alexia directly. According to Carriger mythology someone is able to become a supernatural (vampire, werewolf, etc.) based on the amount of soul they have. They more soul the more likely the conversion into supernatural will go smoothly. Alexia is soulless in that she is unable to be turned into a supernatural. In addition to being able to be turned she also cancels out, or nulls, any supernatural powers when she is in physical contact with them. So if shw holds hands with a vampire, that person will cease to have fangs, will be able to go into the sunlight, that is until Alexia lets go then they revert to their supernatural state. I really thought that Carriger did a great job putting a twist on the popular vampire / werewolf legend. It was a little confusing at first because the book was written as though we, the reader, would already be familiar with the world in which the book takes place. Don't give up. Upon continuing to read you realize that all the questions you have are slowly answered. 
 I also really liked Alexia as a character. Sometimes when you read about the outspoken characters who go against the norm of society, they can be quite annoying. Trying too hard to prove that they are different and they like being different. Alexia just is. It's clear that she doesn't ponder too much about what others think. She lives with a family who make is known on more than one occassion how much of a spinster she is and will probably never marry because of her looks, but if she ever had issue with this it was dealt with off the page long ago. She's also quite intelligent. She knows what she's talking about and can carry on a good conversation about new technological advancements. She doesn't pretend to be something she's not just to reassure people. 
 Her love interest in the books, Lord Maccon, is really the typical alpha male. I personally would have liked to have seen their relationship from the beginning. There are plenty of references to when they first met, but by the start of the book we are quite of few months in to their acquaintance and you can see their feelings are already established, if not declared. I would have liked more of a build up of the relationship that we find in many Urban Fantasy books, where it might take a couple books before the couple actually gets together. 
 Lord Maccon is charged with finding out why rogue vampires and werewolves have been disappearing. Of course Alexia feels the need to try to help out in her own way and ends up getting in over her head when she becomes the target of a mysterious man. 
 I look forward to reading the rest of the series. I only hope that it continues in the same witty way it started. Until Then!