The existence of the seven heikō come as a shock to Tristan when Mamoru tells him of their existence in Moon Child. For as long as he's known Ash, she never once said anything about the heikō, the group the pythia belong in. That's because Ash doesn't remember them, another Yukihime scheme. Very little is known about the heikō right now, where they come from or how many still reside in the world. As a general rule they have little dealings with any race outside of their own.