Math class

You enter into the classroom just before the bell rings. You find an empty seat and sit just as Ms Ren starts her class. Ms Ren is a strict asian futa with straight black hair, pale skin and red glasses. Her tight suit skirt reveals the shape of her cock between her legs.

She writes on the blackboard an equation and turns around to face the class.

"We saw how to resolve these kind of equations last week and I want to make sure you all pay attention in my class so one of you is going to come to the board and will have 30 seconds to give me the answer of this equation. This person will be..."