Quills and shavings are small fairy-like creatures that do not get along. Both are able to use magical spells without use of a swatch, though they use their energy to do so, and may vanish if they use too much. These are spirits, and one could think of them as manifestations of "matter" and "antimatter" of the imaginary plane, as their powers are equal and opposite.
Quills are humanoids that often have animal features. They are connected to life, and their powers are strongest in places with more life energy, namely rainforests and temperate forests. Due to their animal features and sharing their natural swatch abilities, they're often associated with kanvas.
Shavings are demon-like creatures connected to decay, similar in nature to zombies or vampires. Their powers are strongest in desert environments. They are parasitic, feeding on the life energy of other beings. A shaving may turn into an imprint by consuming an entire soul, which usually appears like a faded or miscolored variant of the original body.