Re: Aggressive aikidoka
Me too missed the original post.
Contract or not, there's no way I'd be car pooling with a person like this, just don't pick him up anymore, or don't go to him for a lift.
The person in question obviously has issues, you need help in resolving your situation, nothing wimpy about explaining this to your sensei and asking for help, espcially since you have only come into contact with this person through the dojo.
If they persist in this manner, go to the police.