Common hallmarks are romantic relationships between humans and vampires, shapeshifters, ghosts, and other entities of a fantastic or otherworldly nature.
What's typical in a PNR book:
Urban fantasy is a sub-genre of fantasy defined by place; the fantastic narrative has an urban setting. Many urban fantasies are set in contemporary times and contain supernatural elements. However, the stories can take place in historical, modern, or futuristic periods. The prerequisite is that they must be primarily set in a city.
New-adult Fiction or post-adolescent literature is a recent category of fiction for young adults first proposed by St. Martin's Press in 2011. St. Martin’s Press editors wanted to address the coming-of-age that also happens in a young person’s twenties. They wanted to consider stories about young adults who were legally adults, but who were still finding their way in building a life and figuring out what it means to be an adult.
"emerging adults who are navigating career, love and family in a 24/7 connected world."