Extraordinary you/FF/Taekook

Kim Tae Hyung, a high school boy who is the only child from a rich family, has congenital heart disease. One day, he wonders why her memory keeps disappearing. he finally realizes that he is a character in the cartoon, and decides to find her real life and love. Meanwhile, a character that doesn't even have a name, Seuri high school's student Number 14, lives like the background of the other characters, but his life slowly changes after meeting Kim taehyung. They begin their mysterious adventure to find out the secret of the romance cartoon world, and they try to get their independent lives back.