Spring in the Deep Mountain (1985)

Original title: 깊은 숲속 옹달샘

In a farm, there live a master Dae-Hyeon, Ji-Ae, and a mute Ka-Ya whom they love like a daughter. Also, there is Hyeop who teaches them how to ride a horse once every week. One day, Ka-Ya comes to realize what is sex on the moment of witnessing the scene in which Hyeop is raping Ji-Ae, and she warns Hyeop to don't do that. Surprised, Hyeop runs after and rapes her, and since then, Ka-Ya falls in love with him. Hyeop is move up by Ka-Ya's sincerity and by the time he comes to feel love for her, their relations is disclosed and Hyeop and Dae-Hyeon fight a duel because of it. Shocked at it, Ka-Ya is recovered to speak again. Later, Hyeop and Ka-Ya leave the house as companions of life.