I will start by saying what I liked most about this drama was Gong Yoo. I loved him so much in coffee prince, that I just wanted to see him in something else. I couldn't help but be charmed by him as Tae In. The character was so sweet, playful, and heartbreaking all at once. It's his character that kept me watching. I thought Gong Hyo Jin played her role well too, and loved the chemistry between Na Bori & Tae In, but I didn't exactly love her character. Na Bori was frustrating to watch at times, often silly, and towards the end I found her actions to be almost mean. I also wasn't impressed by the chemistry between her and Ji Hyun Woo. Kim Da Hyun was so passive that he was boring, and they never had any great romantic moments together. There's one scene that I think was supposed to be touching, but I think he came across more as a creepy stalker. Another thing that I didn't particularly like were all the class subplots. Their stories were sometimes sweet, but usually corny, and often felt like time fillers. I can't say that I honestly cared about any of those characters except for Choi Yeo Jin, who was a more interesting rival than Kim Da Hyun. In spite of the slightly taboo topic, this is a very basic romance, with family disapproval, and love squares that you've very likely have seen before. There are many Tae in scenes that I could see myself watching again, but not much else. Gong Yoo is the main reason I would ever recommend this drama. His transformation from a troubled and rebellious teen to a maturing young man, and his struggle to deal with his forbidden love, was truly an impressive performance.