Hwa Sa sang a part of the famous OST "We All Lie" from 'SKY Castle'.

The song, which has helped bring the tvN drama to the masses' attention, was briefly covered by the MAMAMOO vocalist on the March 22nd episode of 'Yoo Hee Yeol's Sketchbook'. The song was chosen by Hwa Sa as a song "most suited to"  her taste, a song she simply described as: "This Song, My Song." 

When the audience wanted her to perform her own rendition of the song, Hwa Sa remained seated in her chair and sang the main verse and chorus of the OST. Check out the video below for the full clip!