context: Ji-ho is a promising pianist, studying and playing abroad for years. But one night she had a stage fright and never recovers. In despair, Ji-ho comes home and meets her old classmate Sung-ryong. Once a very bright boy, Sung-ryong had an accident and now he is in late 20s with the mind of a six year old. He is very forgetful, but he has never forgotten his first love Ji-ho. Other half of Sung-ryong's dumb mind is occupied with his only family younger sister Jee-in. To take care of her, Sung-ryong sells toasts in front of Jee-in's school. But Jee-in is embarrassed of her idiotic brother and ignores him. And Sang-soo is Sung-ryong's old friend who understands Sung-ryong's innocent mind. But he inevitably falls to the world of gangsters. Ji-ho is still in her slump, Jee-in falls sick and Sang-soo gets involved in a bloody dispute. But all of their agonies are miraculously saved by Sung-ryong in a way nobody has forseen.
question: what instrument is ji-ho's talent?
answer: Piano