Lee Su-jeong, formerly known as Baby Soul, is a South Korean singer and a member of South Korean girl group Lovelyz under Woollim Entertainment. She firstly released digital single with "Stranger" on November 23, 2011 prior to debut as a member of girl group Lovelyz in November 2014.

Lovelyz (Korean: 러블리즈) is a South Korean girl group formed in 2014 by Woollim Entertainment and is the company's first girl group. The group consists of eight members: Baby Soul, Jiae, Jisoo, Mijoo, Kei, Jin, Sujeong and Yein. Their debut album, Girls' Invasion, was released on November 17, 2014.