Gender: Female Born: September 14, 1968 (Age 21 in 1988) Family: Father: Sung Dong-il, Mother: Lee Il-hwa, Second Younger Sister: Sung Deok-sun, Third Younger Brother: Sung No-eul Education: Seoul National University, College of Education Nickname: Ssangmun-dong Madwoman

Gender: Male Born: 1972 (Age 17 in 1988) Family: Father: Sung Dong-il, Mother: Lee Il-hwa, First Older Sister: Sung Bo-ra, Second Older Sister: Sung Deok-sun Education: Ssangmun High School (All-boys) Features: The most normal person among the three siblings.

Gender: Male Born: March 5, 1971 (Age 18 in 1988) Family: Father: Kim Sung-kyun, Mother: Ra Mi-ran, Older Brother: Kim Jung-bong Education: Ssangmun High School (All-boys) Nickname: Jung-pal Features: A 'bad boy' type who complains and curses about everything in the world and acts prickly, but eventually gives in. He has a secret crush on Deok-sun.

Gender: Male Born: October 8, 1971 (Age 18 in 1988) Family: Father: Choi Moo-sung Education: High School Graduate Nickname: Heedong-ie Features: A national treasure-level Baduk player in South Korea. He is currently in love with Deok-sun.

Gender: Male Born: September 17, 1971 (Age 18 in 1988) Family: Mother: Kim Sun-young, Younger Sister: Sung Jin-joo Education: Ssangmun High School (All-boys) Nickname: True Human, Model Student Features: He has a crush on Deok-sun's older sister, Sung Bo-ra. He seems to be the most normal person in Ssangmun-dong.

Gender: Male Born: January 28, 1972 (Age 18 in 1988) Family: Father: Ryu Jae-myung (Dean of Students) Education: Ssangmun High School (All-boys) Nickname: Salamander Features: He wears glasses.