Question: To which group does the singer, who stars with Lee Sang-woo in the TV series All About My Mom belong ? 

Context articles: Don't Hesitate
Life Is Beautiful (2010 TV series)
Searching for the Elephant
Feast of the Gods (TV series)
All About My Mom
Han Joo-wan
Eugene (actress)
Happy Home (TV series)
Goddess of Marriage
Kwon Yul (actor)

Don't Hesitate () is a South Korean television series starring Lee Tae-im, Lee Sang-woo, Kim Young-jae, and Bae Min-hee.
 The morning soap opera aired on SBS on Mondays to Fridays at 8:40 a.m. from October 5, 2009 to February 26, 2010 for 98 episodes.
Life Is Beautiful () is a 2010 South Korean television series starring Song Chang-eui, Lee Sang-woo, Lee Sang-yoon and Nam Sang-mi.
 It aired on SBS from September 11 to November 7, 2010 on Saturdays and Sundays at 21:45 for 63 episodes.
Searching for the Elephant (; lit.
 "Penthouse Elephant") is a 2009 South Korean psychological thriller written, directed and produced by S.K. Jhung (a.k.a. Jhung Seung-koo).
 It stars Jang Hyuk, Jo Dong-hyuk and Lee Sang-woo as three male friends who deal with sex addiction, anxiety and other contemporary disorders.
Feast of the Gods () is a 2012 South Korean television series, starring Sung Yu-ri, Seo Hyun-jin, Joo Sang-wook and Lee Sang-woo.
 The series follows the fate of two girls whose identities were switched and later become rival chefs of traditional royal cuisine.
 It aired on MBC from February 4 to May 20, 2012 on Saturdays and Sundays at 21:50 for 32 episodes.
All About My Mom (; lit.
 "Please, Mom) is a 2015 South Korean television series starring Eugene and Lee Sang-woo.
 It airs on KBS2 every Saturday and Sunday.
Han Joo-wan (born January 10, 1984) is a South Korean actor.
 He began his acting career in indie short films such as Leesong Hee-il's queer "Suddenly, Last Summer" and Lee Sang-woo's "Exit" (the latter from Jeonju International Film Festival's annual "Short!
 Short!
 Short!"
 omnibus project).
 Han rose to mainstream popularity in 2013 in the highly rated ensemble TV drama "Wang's Family", which led to him being cast in 2014 period drama "Gunman in Joseon".
Kim Yoo-jin (born March 3, 1981), professionally known as Eugene, is a South Korean singer, actress and presenter.
 She is best known as a member of South Korean girl group S.E.S..
Happy Home () is a 2016 South Korean television series starring Kim Yeong-cheol, Won Mi-kyung, Kim So-yeon, Lee Sang-woo and Lee Pil-mo.
 It aired on MBC every Saturdays to Sundays at 20:45 (KST) for 51 episodes from February 27 to August 21, 2016.
Goddess of Marriage () is a 2013 South Korean romantic comedy-drama series starring Nam Sang-mi, Kim Ji-hoon, Lee Sang-woo, Lee Tae-ran, Kim Jung-tae, Jo Min-su, Kwon Hae-hyo, Jang Young-nam and Jang Hyun-sung.
 It premiered on SBS on June 29, 2013, and ended on November 3, 2013, airing every Saturday and Sunday at 21:50 for 36 episodes.
Kwon Se-in (born June 29, 1982), better known as Kwon Yul actor.
 He made his acting debut with a leading role in the 2007 high school sitcom "Mackerel Run".
 Kwon is best known for his roles as Seo Ji-seok on the daily soap opera "Angel's Revenge" (2014), in the blockbuster period film "" (2014), and more recently as Lee Sang-woo in the hit romantic comedy series "Let's Eat 2" (2015).
 In 2017, Kwon starred in legal thriller drama "Whisper" alongside actress Lee Bo Young and Lee Sang-yoon.