Sisters Girls' Generation Jessica and f(x) Krystal showed off their amazing abs.

On March 21, Jessica revealed her great body line and abs for the W magazine.

She is wearing a lace top and white skinny jeans and shows off her amazing abs, showing her feminine and sexy side.

Sister Krystal revealed her body line through Vogue Girl magazine. She wore a street casual look with a bright colors. Her abs made her look healthy and young.

Many fans praised the sisters for their hard work in creating health and beautiful body lines.