http://yaraon.blog109.fc2.com/blog-entry-5351.html
CHANGE! is owning!!!
EDIT:
Its TRIVIA TIME!
Look closely at the Chihaya's "mother":
Vanishing?
Its Chihaya from a future where there is no idols (and no coffee) and has traveled to the past to prevent a disaster changing the time line of events.
Btw, was Chihaya sheding tears or mercury? Perhaps, she is a magus...