One of the things that are claimed in the book by the main character and may make an impression is that Vatican has a substantial percentage of population with homosexual tendencies (one third). Some priests and soldiers are celibate and some are active. I have no idea if this is correct, but to be honest I do not particularly care. 
 I just think that anybody who is allowed to live in Vatican is lucky enough to be surrounded with so much beauty and incredible art. 
 The fact that the two main characters are gay gets out of the way soon. It is actually emphasized the case that this is not their main problem. One of them has lost his lover 12 years ago and this is eating him inside. The other one has lost his purpose in life and keeps running away from everything that matters. Both they are lost. 
 Alain is an active member of the Swiss Guard while Cris has just joined. The Pontifical Swiss Guard is responsible for the safety of the Pope and serves as the de facto military of Vatican City. It is one of the oldest military units in the world. 
 When Alain is asked to act as Cris' mentor, he is not sure that this is the best idea. His life is a constant battle. He has vampires, ghosts, demons and ghouls to fight and other paranormal creatures which are flooding Rome, Tiber and its catacombs. Soon he will realize that the main reason they put them together is that Cris has been chosen to join Alain against the supernatural threats. 
 Alain mission and true purpose is a secret. Nobody in the Swiss Guard knows why he keeps disappearing in his small office or outside the Vatican, why he keeps coming back with bloody and torn clothes, why he is not really interested in his appearance, why he talks only to the Pope and why his superior leaves him alone. The other soldiers are most of the times scared of him. 
 "He is no Christian brother of mine", one said to Cris warning him about Alain. 
 Poor lonely Alain is trying very hard to fight his attraction for Cris, to push him away and to keep him in an oblivious, normal life where monsters do not exist. But of course destiny has other plans for these two soldiers. 
 "I know what I saw. You said vampires, you said the word", angry Cris shouts at Alain. 
 Soon, monsters will be in the house and Cris needs to learn to play the game fast. He will have a crash course in history, dangerous creatures and how to avoid them, vampires: how they attack and how you attack back etc. 
 Vampires in this book are not your nice, sexy, attractive type. They are dirty, smelly, violent, bloody, nasty night creatures. In order to be destroyed, they need a little bit of faith, a little bit of holly water, bullets, silver and maybe some cheap vodka. You may not like them, but they play a huge role in our story. 
 There is lots of gore and blood and fluids, but as a matter of fact I found more disgusting a scene of a rape attempt. An old priest is trying to rape one of the main characters after he drugs him. Absolutely sickening. 
 The secondary roles are really well developed. 
 - Lotario, a priest who is helping Alain. He is a chain smoker with a strange sense of humor. A true warrior who can also do a bit of miracles. 
 -Angelo, a gruff, veteran of the carabinieri who acts as the conduct with Italian police. 
 - Luca the major who truly loathes Alain and makes Cris' life miserable. 
 - Linhart the vampire 
 -Pope 
 There are a few twists in the story and a big revelation concerning Alain's old lover in the end which will leave you breathless. 
 I am not sure, if this book is a paranormal romance or a mystery book with horror elements. Whatever you call it, it worked for me. Needless to say, the book absolutely absorbed my attention and it is one of these books that I finished in one sitting.