Ongoing El no es mi hermana; She's Not My Sister; 동생이 아니야

For years, SEO-HEE has had a crush on JI-HO, a childhood friend who is more like an older brother. One day, she tries to make JI-HO fall for her through a hypnotic spell, and he goes along with it to keep her from leaving. But how long will he be able to keep up the act?