femmaster

1. Another feminine form of master
2. Female described master

3. Fem abbreviated from feminine placed in front of the word master

A master and his femmaster reign supreme over their territory.

Mastress

1. Obsolete form of mistress.
2. A woman, specifically one with great control authority or ownership
3. Female companion to a master
4. A woman well skilled or expertise in something

Mastress Trish, is a master of the art of karate.
Loretta is the Mastress of ceremony tonight