The story revolves around Goo Jae Hee, a Korean girl living in the United States. One day, she sees a track and field competition on TV, and is attracted to one of the high jump competitors, Kang Tae Joon. She begins to idolize the young athlete and eventually transfers to Korea to attend the same high school that Tae Joon attends after he has an accident that could end his career. Tae Joon has suffered an injury and appears to be on the verge of giving up the sport altogether when Jae Hee shows up at the boys-only boarding school. There's a catch, however: Tae Joon attends an all-boys school and Jae Hee must disguise herself as a boy to get in and starts sharing a dorm with him. She is a big fan of him and all she wants until the end of the drama is for him to compete like he used to; from the beginning to the end of the drama she does EVERYTHING for him, supporting him in everything she can. At first Jae Hee's presence is a nuisance for Tae Joon, who spends a lot of time avoiding her presence and wanting to kick her out of the room, but later a friendship is formed that turns into love when Tae Joon realizes the reality of the roommate's situation. In the middle of this whole story she has to hide her real identity, unlike other dramas in this style she is discovered by Tae Joon in a few episodes and he ends up kind of hiding that he knows she is a woman and helping her to hide that fact without her knowing.
I didn't watch the Japanese version so I can't say between the two, but honestly I started watching this drama because of Minho from SHINee, yes that was the main focus. If you expect a great romance and kissing scenes (there are kissing scenes, but they are sooo scarce), this drama is not for you! Now, if you want something to laugh about, have fun ~maybe get emotional, To the Beautiful You is a great choice! The drama tells a story more about friendship and overcoming and not so much about love, with hilarious scenes and sometimes quite silly... The characters are super charismatic, fun and each one has their own story and their reasons for being there.