I should note that Felix can see astral forms as well, however, he might interpret it differently than Paul does.

1: Blood scent
Felix - ivy.
Irvine - old leather.
Diaval - warm earth after rain.

2: Astral form
Felix - vines and leaves wrapping around him and obscuring him.
Irvine - has the head of a golden retriever :D
Diaval - MOAR feathers everywhere!