You complied with her order, which unfortunately killed your view of her cleavage. That's ok, her face was beautiful enough! But there was more than just her beauty right now. There was also a power. An authority. The same power she was exuding at the end of your fantasy had carried over into real life. She leaned over you and lectured you on the situation with her account, and what you needed to do.
She sent you back to your office with a huge to-do list, a pile of paperwork, and a very full chastity belt. Also, with wild thoughts swirling in your head. You were obviously able to fantasize about Shy, but what if there was more. What if she was the one? What if she was Mistress Fire? She certainly was good at giving directions and exuding power. Could it be? Also, Mistress Fire hadn't made any effort to contact you after you told her the chastity belt was on. Why would that be? You knew you hit her deadline this time!