Dong Hyun, Seok Gu, Sang Min and Young Je are typical adolescent high school boys deeply curious about sexual matters. When a female apprentice teacher, Ms. Kim Yoo Ri (Kim Sun Ah) begins teaching at their all boys’ school, she captures the lust and imagination of four of her students, who cannot stop fantasizing about her.

Dong Hyun’s secret 'love' for his teacher is shattered by news of her affections for another teacher Byung Chul (Lee Beom Soo). Yoo Ri has already fallen for the homeroom teacher, Byung Chul, and has her own daydreams about what it would be like with him. Unfortunately, Byung Chul has forsaken love in his life, and is immune to her come-ons. Yoo Ri must get him to accept her advances, while rejecting the rapid-fire advance of her four students. This comic love triangle erupts into an unforgettable ending.