The only real difference I believe is where she is located in the castle. As the "botanist" she is in the house with Meredith. As a slave she is located in the Castle Quarters in the last room on the left. Other than that there is only some very minor dialogue differences in both scenes (as the slave she calls you "master"). You can also ask her to "bounce" up and down for you as a slave, but that produces no benefit (in terms of a scene) and seems rather useless. Both scenes are available for whichever way you decide to go.Thanks mate!
And should I make Erika a slave or a botanist?
What are the pros/cons of this choice?