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Young-sim is a fourteen-year-old girl who has a round face, round eyes and a pony tail. Her boyfriend Wang Gyeong-tae follows her incessantly. He is considered ugly and stammers when he speaks, but he deeply loves Young-sim. Young-sim treats Gyeong-tae coldly. However, Young-sim displays considerable jealousy upon discovering Gyeong-tae was with another girl. Her mean best friend and her sister Sun-sim add humor to the story.