Both about an older sister trying to protect/save their younger sister from a kidnapping.

Description of Manhole:
A serial killer has been terrorizing a neighborhood in Seoul, and in the span of 6 months, 10 people have disappeared without a trace. He uses a manhole to trap his victims. His latest abductee is Soo Jung, a 14-year-old girl, and her older sister Yeon Seo is desperate to find her before time runs out.