Lee Joo-heon (born Lee Ho-joon on October 6, 1994), better known by the mononym Jooheon, is a South Korean rapper and songwriter.
 He is a member of South Korean boy group Monsta X, formed during the 2014 Mnet's survival show "No.Mercy".
Boyfriend (Korean: 보이프렌드 ) is a South Korean boy group formed by Starship Entertainment in 2011.
 They are the first boy band to have twin members.
 The group consists of Kim Donghyun, Shim Hyunseong, Lee Jeongmin, Jo Youngmin, Jo Kwangmin, and No Minwoo.
 They debuted on Mnet's "M!Countdown" on May 26, 2011 with "Boyfriend".
Jung Taek-woon (Hangul: 정택운 , born on November 10, 1990), better known by his stage name Leo (Hangul: 레오 ), is a South Korean singer, songwriter and musical theatre actor, signed under Jellyfish Entertainment.
 Known for his high-pitched, sharp, and clear vocals, Leo debuted as a member of the South Korean boy group VIXX in May 2012, and began his acting career in 2014 in the musical "Full House" as Lee Young-jae.
 In 2015 he began his songwriting career, and with VIXX member Ravi formed VIXX's first official sub-unit VIXX LR.
History (Korean: 히스토리 ) was a South Korean boy group formed by LOEN Entertainment in 2013.
 They debuted on April 26, 2013 with "Dreamer", featuring the narration of their labelmate IU.
 They were LOEN Entertainment's first boy group.
 They officially disbanded on May 12, 2017.
Lee Jin-ki (born (1989--) 14, 1989 ), better known by his stage name Onew, is a South Korean singer and actor.
 Born in Gwangmyeong, Gyeonggi-do, Onew was discovered at the 2006 S.M. Academy Casting and signed the contract with S.M Entertainment the day after his audition.
 He debuted as one of the lead vocalists of boy group Shinee in May 2008, who went on to become one of the best-selling artists in South Korea.
This is the discography of South Korean boy group Seventeen.
 Seventeen (Hangul: 세븐틴), also stylized as SEVENTEEN or SVT, is a South Korean boy group formed by Pledis Entertainment in 2015.
 They have released one album and four EPs.
Shinee ( ; Korean: 샤이니; Japanese: シャイニー; stylized as SHINee) is a South Korean boy group formed by S.M. Entertainment in 2008.
 The group is composed of five members: Onew, Jonghyun, Key, Minho and Taemin.
Lee Ki-seop (Korean: 이기섭 ; born January 17, 1991), commonly known as Kiseop, is a South Korean singer, dancer, actor and model.
 He is best known for being a member of South Korean boy group U-KISS formed by NH Media in 2008.
 He joined U-KISS in November 2009.
Cho Kyu-hyun (born February 3, 1988), better known mononymously as Kyuhyun, is a South Korean singer and musical theatre actor.
 He is best known as a member of South Korean boy group Super Junior, its sub-groups Super Junior-K.R.Y., Super Junior-M and a former member of the South Korean ballad group S.M. the Ballad.
 He is one of the first four Korean artists to appear on Chinese postage stamps.
SF9 (Korean: 에스에프나인 ; shortened from Sensational Feeling 9) is a South Korean boy group formed by FNC Entertainment.
 SF9 is the company's first dance boy group to ever debut.
 SF9 debuted on October 5, 2016 with the release of their first single album "Feeling Sensation".

Question: What company formed the South Korean boy group of which Lee Jin-Ki is a part?
Answer: S.M. Entertainment