I have been teaching at a small dojo for several years. I don't charge a fee, the students manage the dojo operation. I have not run into any problems until recently. The problem is a new student who has done some years of Aikido. He has become disruptive and is manipulating the dojo. Here's what is happening. The new student is really demonstrating a Alpha male challenge to me. He is arrogant because of his experience and has a very controlling personality. He constantly challenges me at ever corner. He likes to sabotage and undermine my position as a sensei. He has this attitude that I am some how his prison bitch. I don't outwardly slap him down. I do take his abuse because I don't react to his behavior as if he is my prison bitch. I don't think it is an appropriate thing to do in an Aikido class. I don't have the opportunity slap him down verbally privately. Lately, he bring in weapons not part of Aikido and dangerously (mocking) threatening postures toward me as part of him trying to be dominate. It is not my dojo. It is the students dojo who asked me to teach. The students haven't moved to kick him out because it doesn't directly affect them.

I want to live the dojo, but until the student elect the other guy and tell me they want him, I still feel obligated and have a responsibility to them.

What is a sensei like me who isn't into the Alpha male non-sense to do?