Constance was the manager of the rock band Ladyheart.
When Sam and Dean Winchester find out that Constance represents Vince Vincente, they contact her and arrange a meeting inside a restaurant. They pose themselves as an inspiring music band, but Constance doesn't believe them.
They admit they need to know where Ladyheart is playing tonight's concert, warning her that Vince is not Vince anymore, but the Devil. Not only does Constance not believe the accusation, she is also not afraid of the thought. She admits that Vince makes her feel uncomfortable, but it is her job to make "saints out of devils", and she will not betray Vince who is a playing client.
When Sam and Dean refuse to back down, she threatens to scream on them and alert all the restaurants' patrons, in order to get them in trouble. Sam and Dean back away.