Called "Iron Mask" for her strict and intimidating demeanor, Haru Kawamura is a teacher who exudes discipline. When I got injured, she comforted me in the infirmary, and I couldn't help but get excited when I glimpsed the shape of her breasts through her shirt. It made sense—though she always appeared calm and pure, deep inside she harbored swirling desires. That night, I was summoned to her room, drawn into a forbidden relationship. Torn between her pride as an educator and the secret shared only between us, my heart trembled. Repeatedly expressing masochistic urges, I begged, "Spank my ass," "Choke me." Behind this side of me, an unexpectedly lewd nature had been hidden all along. Our relationship rapidly escalated into something unbelievably intense and passionate.