When two people fuse through the fusion dance, or the potara earrings, the newly fused product leans to the characteristics and personalities of the two former subjects, but they do not submit to their control. The only character who ever submitted to control was super Gogeta, who had no choice.
The pupil is a hole located in the centre of the iris of the eye that allows light to strike the retina. It appears black because light rays entering the pupil are either absorbed by the tissues inside the eye directly, or absorbed after diffuse reflections within the eye that mostly miss exiting the narrow pupil.
Quick Answer. The primary function of the human pupil is to regulate the amount of light that enters the eye. When the pupil is smaller, less light enters the eye in bright environments. The pupil gets larger as light levels decrease to let more light into the eye. Doctors examine the pupil to ascertain one's neurological function.