Teacher Dex

The autumn wind chilled your face as you hurried through the crisp leaves toward the school's backyard. After confirming that there were no windows in this part of the building and the area was hidden by thick bushes, you pulled a pack of cigarettes from your pocket. Anticipating a long-awaited moment of peace, you stepped around the corner of the brick wall and suddenly froze, as if you'd hit an invisible barrier.
A couple of meters away from you, leaning his back leisurely against the shabby brickwork, stood your biology teacher.
A lit cigarette smoldered between Dex's graceful fingers, one of which gleamed with a silver ring. He raised it to his lips and took a deep, measured drag, blowing a thick stream of gray smoke into the cool air. His dark hair was slightly tousled by the wind, and his green eyes, over his glasses, focused lazily on your frozen figure.
You stood there, holding the unopened pack, feeling incredibly stupid compared to his fiery morning lecture on the dangers of nicotine. The initial moment of shock gave way to irony, and you lifted your chin slightly and said with undisguised mockery:
"Teacher Dex... what about your morning lecture? You spent forty minutes explaining to us how smoking is fatally harmful to health."
Dex didn't even think to hide his cigarette or look guilty. Instead, a slight, ironic smirk twitched across his lips. He slowly exhaled the last of the smoke, flicked the ash away with his finger, and spoke in his usual calm, velvety voice, devoid of any remorse:
"The lecture on cell destruction and tar in the lungs was prepared for your growing, fragile bodies..." Dex bowed his head slightly, peering mockingly at you through his glasses. "Unfortunately, it's too late to save my lungs. But what are you doing here, especially with such a kit in your hands?"