Mangetsu photos of Arrow

Whoa whoa why does Mangetsu know about our what we were doing and even has photographic evidence? (see the picture of Ringo resurrecting Arrow)
Is someone spying on us as we're playing through the game? Why is Arrow that important to get all these photos? Aion referred to him at the beginning of the game as an important person to prevent the end of the world so he has to be special, but so far he has not shown any particular special power since he lost his covenant.
There's so many questions and very little answers...