Lee Ok Rim is 15 years old. She likes imaging and has bright personality. She is very frank about her feelings. She also knows that she is pretty and uses that. At home she is the second child who is placed between an older sister who studies well and a twin younger brother. Ok-Rim has a boyfriend Yoo Ah In who is studying painting in high school. Ok Rim also has a long time male friend named Jangwook. Between Yu Ah In and Jangwook she is not sure about her feelings.

Jangwook is stubborn, shy, but cool. Since moving next door to Ok Rim, they have become best friends and knows all of her secrets. Like boys around his age, Jang-Wook likes soccer and gets into mischief. He is also warm and becasue of that Jangwook is popular among his peers.

Yoo Ah In is a sophomore in high school studying painting and Ok-Rim's boyfriend. He makes jokes and is sociable, but does not talk about what is really on his mind. Ah In started paining late, but with intelligence and persistence he has won the several contests. Ah In is mature and smarter than his girl friend Ok-Rim, so he controls their relationship. But, there is rival Jangwook and Ah In tries his best to hold onto Ok Rim's affections.

(Source: http://wiki.d-addicts.com/Sharp_1)

《玉琳成长日记》讲述了主人公李玉琳(14岁)（高雅罗饰演）的家族和朋友之间发生的故事。她有一个成绩非常优秀的姐姐和双胞胎弟弟，从小排行老二的玉琳感觉夹在中间不得宠就产生了危机感.并发起了维护自己位置的战争，性格开朗并知道自己的外表比别人漂亮之后，开始会利用自己的外表了。后来又觉得自己伶俐,理性，所以有时候会耍小聪明，觉得自己不仅仅是一个14~5岁幼稚的小女孩。最大的优点也是最大的缺点是比较诚实，想隐瞒一些秘密，却在脸上挂不住。她最大的关心是"男朋友"、死党旭等人维持着所谓之类的关系，却因为是青春期所以有些害羞。但是因为玉琳的几个朋友含情默默的眼神后，玉琳对旭另眼相看…

Lee Ok Rim 15 yaşında. Görüntülemeyi seviyor ve parlak bir kişiliğe sahip. Duyguları konusunda çok dürüst. Ayrıca güzel olduğunu biliyor ve bunu kullanıyor. Evde, iyi çalışan bir abla ile ikiz bir küçük erkek kardeş arasında kalan ikinci çocuktur. Ok-Rim'in lisede resim okuyan bir erkek arkadaşı Yoo Ah-In vardır. Ok-Rim'in ayrıca Jang-Wook adında uzun süredir erkek arkadaşı var. Yu Ah-In ve Jang-Wook arasında, hislerinden emin değildir. Jang Wook utangaç ama havalı. Komşu Ok-Rim'e taşındığından beri, en iyi arkadaşlar oldular ve tüm sırlarını biliyorlar. Jang-Wook, tıpkı yaşıtları gibi, futboldan hoşlanır ve yaramazlık yapar. O da sıcak ve çünkü Jang-Wook akranları arasında popüler. O da inatçıdır.