2. Submissive Romantic: BDSM

Oh, so that´s what you´re going for? Very nice.
Your Cassandra will still put up her stern front and such, but when you show her some romance she will melt into your dominant arms. She will have fantasies about being tied up, gagged, flogged, led around on a leash etc.

As you push it she will ofcourse have her little tantrums but you just have to show that she can trust you to take care of her as a submissive and she will give herself to you.

Now that you´ve specified how you want her to be mentally. Would you like to change anything physically or would you like us to deliver her?