Character's name: "Self"
Birthday: 08/14/1972
Birthplace: Seongbuk-gu, Seoul, South Korea [now Gangbuk-gu]
Biography:
Yoo Jae-suk (유재석) is a South Korean comedian and television host, commonly called "The Nation's MC" (국민 MC). 

Character's name: "Self"
Birthday: 02/10/1966
Birthplace: Jeongseon, Gangwon, South Korea

Character's name: "Self"
Birthday: 04/25/1976
Birthplace: Hapcheon, South Gyeongsang, South Korea
Biography:
Kim Jong-kook (김종국) is a South Korean solo singer, television personality, and member of the vocal group, Turbo.

Character's name: "Self"
Birthday: 08/20/1979
Birthplace: Seoul, South Korea
Biography:
Haha (하하), born Ha Dong-hoon (하동훈) is a South Korean comedian and singer.

Character's name: "Self"
Birthday: 08/15/1981
Birthplace: Pohang, North Gyeonsang, South Korea
Biography:
Cheon Seong-im (Hangul: 천성임; born August 15, 1981), better known by her stage name Song Ji-hyo (송지효), is a South Korean actress and model. She made her acting debut in Wishing Stairs (2003), one of Whispering Corridors film series. She then received further recognition for her roles in Princess Hours (2006), Jumong (2007), A Frozen Flower (2008), New World (2013), Emergency Couple (2014), and My Wife's Having an Affair this Week (2016). Song is also known for being one of the members of the South Korean variety show Running Man.

Character's name: "Self"
Birthday: 12/08/1986
Birthplace: Dongducheon, Gyeonggi, South Korea
Biography:
South Korean Comedian & Variety Show personality (Entertainer)

Character's name: "Self"
Birthday: 04/07/1986
Birthplace: Goyang, Gyeonggi, South Korea
Biography:
Jeon So-min is a South Korean actress. She made her debut in 2004 MBC sitcom called "Miracle". In 2013, Jeon played her first leading role in the MBC television series Princess Aurora. Wikipedia

Character's name: "Self"
Birthday: 07/14/1985
Birthplace: Namyangju, Gyeonggi, South Korea
Biography:
Lee Kwang-soo (Korean: 이광수; born 14 July 1985) is a South Korean actor, entertainer, and model. He made his acting debut in the sitcom Here He Comes (2008). He then received further recognition for his roles in medical melodrama It's Okay, That's Love (2014), neo-noir film Confession (2014), black comedy film Collective Invention (2015), one-act play Puck! (2016), sitcom The Sound of Your Heart (2016) and drama Live (2018), drama comedy film Inseparable Bros (2019). Besides acting, Lee is also known for being one of the regular cast members of the South Korean variety show Running Man since 2010.