Chizuru-chan Kaihatsu Nikki follows the complete sexual corruption and development of the initially shy and innocent Chizuru. Under the meticulous and perverse guidance of a manipulative older man, she is systematically broken down and remolded into a depraved exhibitionist and public sex slave. The series chronicles her 'development diary,' where each entry marks a new step in her degradation. It begins with simple flashing and forced masturbation in public spaces, quickly escalating to her being fucked raw by strangers in park bathrooms, gangbanged by groups of men who use all her holes mercilessly, and forced to perform oral sex on command for anyone her master chooses. Viewers watch as Chizuru's resistance dissolves into pure, slutty arousal, her mind twisted to crave the humiliation and cum she once feared. The climax of her development sees her joyfully presenting her used, dripping cunt and asshole for public inspection, a perfect fuck-toy completely stripped of her former self, living only to be filled with sperm and displayed for others' pleasure.