Yoon San-ha, known mononymously as Sanha, is a South Korean singer and actor under the label Fantagio. He is a member of the South Korean boy group Astro and a former member of its sub-unit Moonbin & Sanha. From Wikipedia
Production teasers promise that the gender-bender romance will deliver more unpredictable twists in upcoming episodes at 9:50 p.m. KST.