I've never heard of the books before but seeing the book cover makes me think I've seen it in the YA section.
Vampires have become the new bad boys of romance. They seem to have been 'de-fanged' from putrid, undead horrors to tragic, soulless monsters to erotic, tormented souls to gothy, blood-drinking bad boys. When I see a vampire in a current novel, I don't think monster or villain but romantic interest.
I wonder to what extent changing attitudes toward women engaging in physical intimacy have helped the vampire gain popularity. It used to be that since heroines were good, and good women don't just hop into bed, the heroine could refuse the romantic interest and it reflected well on her. Now it seems a three-month-old relationship without any horizontal activity is considered odd.
Enter the vampire: a ready made reason to put off that activity until the writer considers it thematically right. "Oh, I love you John, but I have vowed to destroy your kind/ but you might kill me/ but you might turn me into something I hate/ but you're still in love with your 1,000 old ex!"
This is a book about a 17-year-old-girl and sold to YAs. The main conflict is that love one another, but his passion for her would cause him to kill her if they're anything other than chaste. As a metaphor, that's unsubtle, and it's an interesting message to send to young readers.