MBLAQ, an acronym for Music Boys Live in Absolute Quality) is a South Korean quintet boy band created by Korean pop R&B singer Rain under his label J.Tune Entertainment. The group debuted in October 9, 2009 at Rain's Legend of Rainism concert. On October 14, 2009 the group released their debut single album, "Just BLAQ", which topped various on-line and off-line music charts in South Korea.
Having trained for two years, MBLAQ was first announced on 21 September 2009, with an appearance on Nylon magazine. The group appeared alongside Rain, in his Legend of Rainism concert. They performed various songs from their produced EP, Just BLAQ and were met with praise. The group released teasers for their debut song, "Oh Yeah" on October 12, with the music video being released two days later. Coinciding with the music video, MBLAQ's debut single album Just BLAQ, was released on the same day, topping various charts in South Korea. The next day, the group made their broadcast debut on M.net's M!Countdown, performing "Oh Yeah".
In early December, the group debuted in Japan, following their performance during Rain's fan meeting- resulting in a documentary being produced surrounding their stay at Japan. Later in the month, the group commenced promotions for their follow up track, "G.o.o.d Luv", with the music video being released December 10, 2009. On December 15, it was announced that the group would be part of Season five of the Idol Show (Idol Corps, She Has Arrived!), with the first episode airing a day later.
* Full Name: Yang Seungho.
* Date of Birth: October 16, 1987 (1987-10-16) (age 22)
* Position: Leader, Vocalist
* Full Name: Jung Byunghee
* Date of Birth: November 6, 1987 (1987-11-06) (age 22)
* Position: Main Vocalist
G.O. is a former member of Korean group, TYKEYS, a 3-member band that debuted in 2007.
* Full Name: Lee Changsun
* Date of Birth: February 7, 1988 (1988-02-07) (age 22)
* Position: Vocalist, Main Dancer
Joon acted in the movie Ninja Assassin as the younger version of Rain's character Raizo.
Cheondoong / Thunder
* Full Name: Park Sanghyun
* Date of Birth: October 7, 1990 (1990-10-07) (age 19)
* Position: Rapper, Lead Dancer, Vocalist
Cheon Doong (Korean term for Thunder) is the younger brother of 2NE1 vocalist Sandara Park. Having trained under Loen Entertainment, Cheon Doong transferred to J.Tune to then replace member Sang Bae after he left before the group's debut. His sister, Sandara Park, is a former Korean expatriate who once starred in movies and television shows in the Philippines. Like his sister, he lived in the Philippines and is fluent in Tagalog and is also conversational in English. He rapped on Lyn's song "New Celebration" together with Dok2
* Full Name: Bang Chulyong
* Date of Birth: March 10, 1991 (1991-03-10) (age 19)
* Position: Main Rapper
Mir is the younger brother of actress Go Eun Ah. He recently became part of Makbanshi (Idol Magnae Rebellion) along with the other youngest members of fellow idol groups 2AM, FT Island, U-Kiss, T-Max, and Mighty Mouth. He provided his rapping vocals in An Jin Kyoung's song, "Bad Person".
* Real Name: Kim Sang Bae
* Date of Birth: April 29, 1991 (1991-04-29) (age 19)
He left right before MBLAQ debuted due to personal reasons.