vampires are real, but they are mystical and follow those old rules(can only enter a home if invited in), one day you find a young girl hiding in the shade on your porch, trapped by the sunlight, her pale skin and fangs say it all, but she overly thin body and bruises say a bit more, and that spot of the porch typically gets completely shined in a about an hour, what do you do.

Vampires are public knowledge, and are discriminated, other monsters are too, but they stay hiding.