So... a 2600yr old vampire who finds no greater pleasure than killing women; she prefers it when they struggle, prefers it when they try to escape and she needs to hunt them down. The author does not explicitly state how often she does this, but as she grows hungry after just a few days, it seems to be about a ~weekly occurrence, and with no moral qualms, there really should not have been anything that kept her from having done so from birth, so a death toll above a hundred thousand?
When meeting the human love interest, a dog chasing rabbits is apparently a perfectly apt comparison to justify these murders, and when the human is confronted with the prospect of dating a mass murderer, her response is: "I think I need some time to process this." -> proceeds to process it for about 5 minutes, but then of course have no qualms about continuing their affair. The hormones must be strong in this one.
You would also assume that there must be something absolutely extraordinary about the woman who is able to pacify our vampire's murder instinct for the only time in the last 2600 yrs, but it actually just plays out as a fairly standard romance, a small attraction followed by a few dates (and obviously this is enough development for them to assume that they'll be together for about a thousand more years).
So from the Goodreads summary "When Ero’s true self is revealed, will Annie’s fear win out over her attraction?" The thing though is that Annie never has any fears, she is actually so accepting of Ero as a vampire that at first I thought it was a joke, that Annie just thought Ero was pulling her leg.
I am just left kinda wondering why you would write a novella-length story about this.
There could have been some very interesting conflict between having an attraction to a serial killer, and also perhaps some semblance of remorse to know that you have killed thousands of women who are just like the woman you now love. [This of course does not happen, she has no remorse and there is never any conflict].
I like vampires, but I hate the trope (mostly from Buffy?) that vampires don't breathe while at the same time being able to speak and smell. Did they develop some new organs that make sound without air? Yes, I can absolutely believe in immortal vampires while at the same time not accepting
that vampires can speak and smell without breathing. I don't WANT to give points to Twilight (Midnight Sun, really) but that got it right, they breathe to speak/smell but they don't need to to survive.