My friend just told me she is learning how to be a dominatrix?

My friend just told me she is learning how to dominate(ual) she apparently has a mentor teaching her and she is researching...I don't know what to say to her, I find it really weird and she said she doesn't want me to judge her and i'm not but, it is kind of freaking me out..Like why would she tell me this? why would she want to do this? she is really open with her life and I think she is addicted to , she has with almost any guy she goes on a date with and is one of her favorite topics, what do i say?