Watch Beautiful Sister for Free: How to Stream the Movie Online at 123Movies. . Byung Chul, a graduate of a prestigious university, is a preparatory student. He has a crush on his younger sister, Ji-young, who saved her from childhood youth. Jiyoung is dating celebrity manager Jiwan, who was once a big fan of her, but she doesn't love her. By chance, he dreams of a new love with him again, but Ji-wan starts to hinder their love.