Author moods, not sliders
Pose and expression are separate
Section titled “Pose and expression are separate”Where the head is pointing and what the face is doing are solved apart, then combined. A turn of the head carries no feeling; a wink and a smile carry no direction. CoyKoi keeps them independent so an expression you author reads the same whichever way the performer happens to be facing.
That is why you author an expression front on. You are describing what the face means, not where it is.