Actually, Terrina was introduced--she was the female that Jared was with who drained a human while he was "with her". But...this is the problem I sometimes run into having to break this book up in this way- beginning with the previous chapter, several chapters in a row are really meant to be binge read, without time to stop and think about it. Everything that happens, happens fast, and..I can't say too much without giving it away, but suffice to say it doesn't work very well this way, but it does work the way it's meant to be read.

EDIT: Also, I've stated a number of times, Jenna has a problem with her visions when concerning her own life.