C subs often seem a little confused, or shy, or sensitive or unbalanced. They are constantly swinging between "extroversion" and "introversion". Even in mild cases one can see this if looking carefully.

Often they can have long monologues about their own stuff, that is hard for anybody to listen to.

They often seem not present in the moment. But then when they do their own thing it's natural.

Physically they can look "worn out", especially if older, but also young Cs can look that way. Not always though.

Their free spirit is sometimes compensated by a very strict, normal attitude.