This is a book that I read about 20 years ago, so probably somewhere around 2003-2006, I had it borrowed from a library and the copy was pretty beaten down so most probably it was released some years before that. I think I found it in the horror section but I remember it more as an urban fantasy type than traditional horror. I remember it seemed quite thick to me at the time, which means it was probably around 350-400 pages. No memory at all about the cover. I read it in Polish but I’m 99% sure it was a translation, probably from English. It was in first person narration. I think the setting was roughly contemporary to when it was written but there were fantasy elements to it.
The protagonist was a woman in her mid-thirties (?), she was some sort of a paranormal investigator or a covert monster hunter. I vaguely recall her going after a vampire or something similar for majority of the book. The only fragment I really remember clearly was that after a fight scene where she choked someone unconscious she had this internal musings about how TV always shows choking someone to death as easy and quick whereas in reality to kill someone you have to keep choking them for a long time after they lose consciousness. I also think there was a scene in an adult movie cinema where she was meeting someone but I’m not 100% sure on this.
I know this is a long shot as it’s not a lot to go on but maybe someone will have an idea, it’s been bothering me for some time now and I’d love to find it and reread.