Glad to see i'm not the only one infuriated by that teacher.
Having the brides die with a timelimit isn't bad. It ups the tension. Suddenly introducing a secret organisation who sacrifices lives and uses the vampires to further their agendas and make money to, just guessing, try and control the world (because why not?) - that's very generic.
It seems as though the mangaka didn't really know what to do with the story until about a chapter or two ago.
I enjoy this series but this chapter was crap.