Question: Goddess of Fire stars a South Korean actress and singer who debuted in 2001 as the main vocalist of what South Korean girl group?

Context paragraphs:
Kei (singer): Kim Ji-yeon (; born March 20, 1995), commonly known by her stage name Kei, is a South Korean singer and actress.  She made her debut as a main vocalist of South Korean girl group Lovelyz in 2014.  She made her acting debut as the female lead in the web drama "Matching!  Boys Archery" in 2016.

Goddess of Fire: Goddess of Fire (; lit.  Goddess of Fire, Jung Yi) is a 2013 South Korean television series starring Moon Geun-young, Lee Sang-yoon, Kim Bum, Park Gun-hyung, Seo Hyun-jin, Jun Kwang-ryul, Jeong Bo-seok, Byun Hee-bong, Han Go-eun, and Lee Kwang-soo.  It aired on MBC from July 1 to October 22, 2013 on Mondays and Tuesdays at 21:55 for 32 episodes.

Luna (singer): Park Sun-young (born August 12, 1993), better known by her stage name Luna, is a South Korean singer, actress and presenter.  She is best known as the main vocalist and lead dancer of South Korean girl group f(x).  Luna made her solo debut with the extended play "Free Somebody" on May 31, 2016.

Park So-yeon (singer): Park So-yeon (born October 5, 1987), better known mononymously as Soyeon, is a South Korean singer and actress.  She is best known as the former main vocalist and member of South Korean girl group T-ara.

Jung Eun-ji: Jung Eun-ji (born Jung Hye-rim, on August 18, 1993), better known by the mononym Eunji, is a South Korean singer, songwriter, actress and voice actress.  She is best known as the main vocalist of the South Korean girl group Apink.  Jung made her acting debut in the coming-of-age drama, "Reply 1997" in 2012.  She has since had roles in "That Winter, the Wind Blows" (2013), "Trot Lovers" (2014) "Cheer Up! " (2015), in addition to various voice acting roles.  She released her debut solo album, "Dream", in 2016.

Seo Hyun-jin: Seo Hyun-jin (Hangul: 서현진 ; born February 27, 1985) is a South Korean actress and singer.  Seo debuted as the main vocalist of South Korean girl group, M.I.L.K in 2001 and continued until 2003 when the group disbanded.  She contributed songs as a solo artist after the group disbandment before she transitioned into acting in 2006.

Kwon So-hyun: Kwon So-hyun (born August 30, 1994), is a South Korean singer and actress.  She was known as a member of the South Korean girl group 4Minute, under Cube Entertainment.  She is also a former member of the South Korean girl group, Orange.  Before June 15, 2016 (end of her contract with Cube), Sohyun left 4Minute and the record label along with members Nam Ji-hyun, Heo Ga-yoon, and Jeon Ji-yoon.

Raina (singer): Oh Hye-rin (born May 7, 1989), better known by her stage name Raina, is a South Korean singer-songwriter.  She is the main vocalist of South Korean girl group After School and also the leader of After School sub-unit Orange Caramel.  Raina debuted with the group in November 2009 following the release of the group's second single, "Because of You".  She debuted as a solo singer in September 2014 with the single "You End, And Me".

GP Basic: GP Basic (Korean: 지피 베이직 ) was a South Korean girl group who debuted on August 15, 2010.  At the time of their debut, they were considered to be the "youngest" South Korean girl group with an average age of below 13.5.  The age of their youngest member, Janey, caused controversy followed by the debut of a much younger girl group, G-story, who were all below 10 years old.  This led to new broadcasting regulations in South Korea.

Han Seung-yeon: Han Seung-yeon (born July 24, 1988), better known mononymously as Seungyeon, is a South Korean singer and actress.  She is best known as former main vocalist of the South Korean girl group Kara.

Supporting paragraphs: Goddess of Fire Seo Hyun-jin
Answer: M.I.L.K