Class beauty Tsumugi-chan, charming and adorable, makes her appearance—a popular student council member who's always smiling and surrounded by friends. But suddenly, the strict teacher confronts her: "Take off your uniform, we're doing a health checkup," leaving Tsumugi on the verge of tears. Yet the teacher, captivated by her figure, uses the exam as an excuse to expose her more and more. Her healthy, slender body is clearly why she's so popular with boys. Her pubic hair is neatly trimmed, giving a fresh, vivid impression. As ultrasound gel is applied to her belly, she trembles with pleasure under the pressure, tears welling in her eyes. Still, her subtle writhing exudes an increasingly erotic aura. Her anus is slightly open, her labia majora well-developed—her plump, fleshy labia suggest a promiscuous nature. With a vaginal diameter of 4.1cm, is she used to having boyfriends thrusting deep inside? Then, the perverted, overheated teacher suddenly proposes a live sex demonstration for educational purposes. Though Tsumugi resists at first, she soon finds the teacher's erect cock shoved into her mouth, drooling uncontrollably instead of crying. With one deep thrust, he penetrates her pussy, and she begins grinding her hips in cowgirl position, clearly aroused. The teacher's face lights up with satisfaction as the practical lesson ends in creampie ejaculation. Tsumugi whispers, "Let me creampie you next time too," leaving behind a filthy promise as their twisted relationship deepens.