As no word exists for Men who believe in equal rights for men, Mansogynist was created tongue in cheek as all words used to describe Men for Men Rights hold negative connotations.
Loosely taken from the word Misogynist but used not as a negative but a positive to describe Men who believe other Men deserve and don't receive fair treatment in the Courts and Society today.
A man who believes in and stands up for Men's rights when it comes to equality in day to day life and advocates fairness in the courts where, child custody, child support, vagina-mony and other areas where men get taken advantage of by women.
The Male counter part to a Feminist.
If you a man and you believe that women and men should have equal rights, you are a Mansogynist. Also if you advocate equal and fair treatment of Fathers/Husbands/Men in general and in the courts, you are a Mansogynist. There's nothing "sexist/misogynistic/chauvinistic" about it.