something is really going wrong in your dojo.
Normally, such a situation must not evolve
under a responsible sensei. A good aikido teacher has to take of all of his students, and should normally realize very quickly when someone is behaving in dangerous way.
Aikido is also about individual responsibility: If you cannot change the situation, nor your sensei is able to, it is
time to leave this dojo.
The fact that all senior women have already left is quite alarming.
I agree with Deb's third hint. Try this,
but make sure that all people scared of this guy will not practise with him.