“Glass skin is this idea of transparent and translucent skin” Alicia Yoon, founder of Peach & Lily , explained to us back in 2017 at the height of the trend. “It's a sign of youthfulness and it's one of the most strived for qualities in Korea." Yoon described it as "the pinnacle of youthful skin" and, a year ago, claimed that products alone won't help you achieve the super-smooth complexion overnight — at least, until she went ahead and formulated one to help get you there.