Main Characters:

Hikari Hanazono (Krystal Jung) - Is ranked 2nd in the school. She is energetic and kindhearted, but rather dense to more subtle matters, in particular love. Unlike her peers, she comes from an ordinary family and her father is a carpenter. When she was six years old she experienced her first defeat and humiliation when she lost to Kei Takishima in a pro-wrestling match. In order to beat Kei, Hikari convinced her father to allow her to attend Kei's prestigious elite school and strives to defeat Kei at anything, from academics to athletics.

Kei Takishima (Choi Minho) - Kei is Hikari's rival and holds the 1st position in the entire school; he is good at everything he does and is always a smooth winner. Kei has been in love with Hikari since they were children, but Hikari has been too dense to realize his feelings for her. While he maintains a stoic and cool facade most of the time, he loses his composure whenever Hikari is in trouble. He is the son of the CEO of Takishima Corporation.

Jun Yamamoto (Li Jinki/ Onew) - Jun is ranked 3rd in school and is the son of a music producer and a talented vocalist. Like Megumi, he is very possessive of Ryuu and seems to worry Ryuu as much as he worries about the two of them. Jun is rather shy around girls, which resulted in a split personality that enables him to charm almost all women effortlessly. Unlike the rest of his friends, he tends to be quiet and rarely gets involved with any disputes. He also becomes the object of Sakura Ushikubo's love

Megumi Yamamoto (Sul-Li Choi) - Megumi holds the 4th position in school and is the older twin sister of Jun. She and her brother are very close to Ryuu, whom they have known since they were children. Megumi refuses to speak so as to preserve her singing voice and writes what she wishes for people to know on a sketchpad. However, she is shown to speak to Yahiro Saiga, who she turns out to be in love with. When she sings, her voice is so devastatingly powerful that everyone who stands near ends up dazed and disoriented afterward.

Tadashi Karino (Kim Jonghyun) - Tadashi ranks 5th in school and is the son of the school's director. He suffers from a bit of wanderlust, likes to travel alone and do whatever he wants or sees fit. Tadashi seems to end up as the character most comically attacked (frequently by Akira) because of his careless comments or reckless behavior. He enjoys eating sweets, especially food made by Akira. Tadashi is in love with Akira but doesn't know how to tell her so he just keeps quiet. 

Akira Toudou (Victoria Song) - Akira holds the 6th position in school and is very fond of Hikari; as a result, she is very protective of her--especially when it comes to Kei and Hikari being together. She loves afternoon tea and is very fond of cute girls. Akira doesn't realize she is actually in love with Tadashi, and constantly is beating him up (which he takes humorously). She is the daughter of the owner of an airline company. She and Kei were a childhood friends of Yahiro, however her friendship with Yahiro was broken apart due to Yahiro's constant bossiness.

Ryuu Tsuji (Kim Kibum/ Key) - Ryuu ranks 7th in the school and is the son of the CEO of a sports car company. He is an animal lover and is very good at handling children. The twins are unusually close to him because they have been together since childhood. It is hinted that perhaps he is smarter than 7th place (he is shown in an episode to finish 1000 questions in 10 minutes and get them all correct), but spends the majority of the time during exams worrying about Jun and Megumi, who tend to become bored or sleep during tests.

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got a little bit tired....next chapter i will write the other characters.^^