Young Hole: Jeong-gook, who runs a private business, only looks at his son after he got hurt. Seong-sil came as a tutor when Jong-soo became a high school student. Jong-soo, who had no mother, follows Seong-sil as a teacher, sister, and mother. Jeong-gook, who watched this, gradually grows in love with Seong-sil, and the two start a family based on marriage. Jong-soo has already loved Seong-sil as a woman, not a teacher. What will be the future of this family...