It is going to have to be faced upto:
To what extent is it going to be acceptable to involve non consenting people in personal sexual experiences?
And how do you put a line down because this is making non consenting use of other people's bodies. Whether you wish to be in a female toilet because you find the sounds of women peeing and unwrapping tampons to be a highly charged sexual experience, or whether you wish to be in a female toilet because you wish to see yourself as a female among other females who are in a state of vulnerable undress as they only are around other females you are still using those female people's bodies for your personal desired experience and to meet your personal needs. Without care for the impact your use of them may have.
I don't want to be a non consenting prop in the life of someone deemed of a higher status and greater importance than others, in this unequal powered relationship. It's not ok to use women like this.