If faeries have no soul... then how could Aurafeel the emotional turmoil she did in SK? Only someone with a Soul could fell such pain, yes?
Or Aurie was just really, really good at reading Harry and feeding Harry the line he wanted to hear while she pulled the rug out from under the hotel operation.
Toot's loyalty to Harry is there because he too has something within him that makes him capable of liking and befriending Harry.
This is way too Patty Hearst for a Faerie, imo.
So if faerie have no soul, what DO they have?
Other than immortality unless killed? Sentience.