Her first appearence is in manga only, chapter 127 (Vol. 16)
She's Urumi Kanzaki's mom. It's not revealed her first name.
She knows how to make money by playing the stock markets to her advantage. Uses a vast pool of equipment and information to do all of this.
As a mother she doesn't seem to be very caring.. she is more concerned about making money. Urumi's sole purpose in life (according to her somewhat cold and uncaring mom) was to be a source of money, money, and money for her mother.
In fact the big "secret" that was mentioned about how Urumi's mom chose to have her daughter is related to this.
At first, she doesn't care much about Onizuka.. she rather sees him as an obstacle to her daughter's success. Like with some of the other parents in the series, Ms. Kanzaki learns a few things from Onizuka and will behave better towards him later.