Most men who are dominant in real life are looking for balance in sex, and they want to become submissive for that time. But there are also leading women who might be bisexual, who also look for a female dominant to treat them badly.
And this is what a dominatrix is for. She needs to be respected, while her slave obeys her at any times, within certain limits. As this is a role play, the rules need to be set ahead. It is not pleasant for either the sub or the dom if something beyond limits is done, since it ruins the entire adventure. So, when she asks you what your limits are, then you need to be honest and tell her everything. If you do not want to dress up like a baby or a ballerina, if you have claustrophobia, or if you are afraid of needles, you should let her know ahead of time. She will respect that. And when she is close to your limits, or worse, if she has reached them, then you must use the safe word that you have also agreed upon beforehand. And there is likely to be times when she would get close to your limits, since if you do not obey her every time, she will punish you, and those punishments can be harsh, but never harsher than what you can bear.
So, if you are in the mood, then feel free to write the model down here, and she will give you what you want!