High school girls spend their days busy dealing with physical and emotional changes, sharing their private concerns with close friends. Amid these conversations, topics turn to masturbation, eventually leading to deeper intimate relationships. Acting as the "Ona Senpai," you gently guide and teach pure girls who haven't yet experienced sex, introducing them to the ultimate human pleasure—orgasm. Through touching, fondling breasts, sucking nipples, and physical closeness, their minds and bodies gradually open up, trembling as they experience climax for the first time. Watch closely as they discover this intense new sensation.