Our heroine Anna Whitt has extremely sharp senses, but has never understood why. As the novel begins, she finds out that she is the daughter of a fallen angel (and a non-fallen angel) and her life is about to change.
Higgins creates a beautifully constructed world and peoples it with realistic characters, including the hot son of another fallen angel to whom Anna finds herself overwhelmingly attracted. Great, realistic situations and complex, believable characters. Although incredibly readable and enjoyable, it ties in quite sneakily and successfully with adolescent issues (heightened senses stand in for raging hormones, complex parentage for feeling special, and peer pressure as an actual job).
Note for completists: This is the first in a planned trilogy; parts two and three are not yet published, but certainly worth checking out.