Hyein the vocalist of the group, was born in Incheon, South Korea. She has an older sister and an older brother. She likes strawberry and the group EVERGLOW. She is part of Harry Potter lovers, and has a bunch of its books in English and Korean, and also has Harry Potter’s wand.

Hyein became the brand ambassador for Louis Vuitton. She is the youngest to ever do so, at the age 14.