Chen can leap over dead bodies and bring them back to life.
:V
Nekomata maybe, she possesses the dead body right?
Orin however, is a Fire Car (read Kasha I think), a Kasha traditionally is said to resemble a giant bus.
Now that is interesting because Orin has a wheelbarrow. a vehicle by comparison!
Orin is said to be the consumer of dead souls and a pretty pesky creature. In Tokugawa's era, it was said that a tradition for a dead one in the family for at least 1 monk and then 1 family member to light 6 candles throughout the night and not sleep, in order to drive away the Kasha from taking hold of the soul attempting to make their journey to the afterlife.
Kasha is said to possess the body or eat the corpse, varied descriptions include the Kasha being a cat with two wheels attached under the feet, and roll about in flaming fury. (imagine Air Gear, with wheelbarrow wheels) or a chariot of sorts that rides on fiery wheels (a example: watch for the old man in the trio that follows Enma Ai in Jigoku Shoujo)
Also, in certain parts of Japan, I heard...
Tiangou, or Tengu, are forms of Mountain Gods, this may indicate why Aya is so powerful (POFV) instead of some ZUNhax. Mountain Gods are normally giants that lay dormant in the form of towering human featured rocks, or are moving mountains (think the rock giant in Warcraft), and they may or may not employ Tengu to guard their sacred mountain.
Does this indicate Aya used to serve a greater Mountain God (before Kanako) or did Kanako slay the former Youkai Mountain God?