Young-Joo
Young-Joo is a shy bookworm with a snaggletooth and opaque nerd glasses. He is often overlooked by his peers, but he is secretly in love with his classmate, Sun-Ah. One day, Young-Joo decides to finally confess his feelings to Sun-Ah, but he is interrupted by her boyfriend, Jae-Hyun. Jae-Hyun is a popular and athletic student who is everything that Young-Joo is not. He is also very protective of Sun-Ah, and he does not take kindly to Young-Joo's advances.
Jae-Hyun challenges Young-Joo to a duel, and Young-Joo accepts. The duel is held in the schoolyard, and it is a battle of wits. Young-Joo uses his knowledge of books to outwit Jae-Hyun, and he eventually wins the duel. Sun-Ah is impressed by Young-Joo's intelligence and courage, and she realizes that she is in love with him.
Young-Joo and Sun-Ah start dating, and they soon become a couple. They are very happy together, and they enjoy spending time with each other. However, their relationship is not without its challenges. Jae