Question: Timing is the fourth Korean mini-album by the leader and main rapper of what boyband?

Context paragraphs:
Find (SS501 EP): Find (데자뷰) is South Korean boy band SS501's fourth Korean mini-album.  It was released after their Japanese maxi single, "Lucky Days".

Hit Your Heart: Hit Your Heart is the second mini-album by South Korean girl group, 4Minute.  The mini-album was released on May 19, 2010, and contains seven tracks.  "HuH" was being used as the promotional song for the mini-album.  The song debuted at number five on South Korea's Gaon Digital Chart and reached number three for two weeks.  The mini-album debuted at number three on the Gaon Album Chart on May 30.  Promotions for the mini-album in South Korea continued with "I My Me Mine", which later received a single release in Japan.

Timing (EP): Timing is Kim Hyun-joong's fourth Korean mini-album, which was released on July 11, 2014 under KeyEast.

Nobody for Everybody: Nobody for Everybody is the Japanese debut EP / video album by South Korean girl group Wonder Girls.  The title song is the same album name,"Nobody" ～あなたしか見えない～ (ノーバディ , Nōbadi ) , taken from their third Korean mini-album, "".  This is the fourth language that "Nobody" has been released in following the original Korean, then English and Chinese.  The EP consisted of Japanese version of "Nobody", as well as 2012 re-recordings of "Nobody" (Korean and English), "Saying I Love You", and "You're Out" to include Hyerim's vocals, who entered the group in 2010, replacing group's original member Sunmi who rejoined the group in 2015.  The video albums features thirty-six videos (music videos, live performances etc.).

The Boss discography: This is the discography of the South Korean boy band The Boss.  The band has been in the music business ever since debuting in March 2010.  To date, the band has released one full-length Japanese album, one Korean mini-album, two Korean singles, eight Japanese singles, and one sub-unit single.  The band has also participated in singing OSTs of Japanese show and Japanese movie.

Destination (EP): Destination is South Korean boy band SS501's eight Korean mini-album released on May 24, 2010 by DSP Media.  This was also their last mini-album before their contract's expiration.

Can't Stop (EP): Can't Stop is the fifth Korean mini-album (ninth overall) by the South Korean rock band CNBLUE.  It was released on February 24, 2014 with the track "Can't Stop" as the promotional single.  This mini album marks a whole turn on CNBLUE's music.  Its lead singer, Jung Yong-hwa ditches the guitar and plays piano on most of the songs.  The style of this album is, as its leader singer stated on an interview, a bit of brit rock meets melodic pop rock and even Latin melodies that can be heard in Diamond Girl.

Re:Blue: Re:Blue (stylized Re:BLUE) is the fourth Korean mini-album (seventh overall) by South Korean rock band CNBLUE.  It was released on January 14, 2013 with the track "I'm Sorry" as the promotional single.

Voice (EP): "Voice" is CNBLUE's second Japanese mini-album.  "Y, Why" is the only song which is not English.  "Y, Why" is a Japanese song which was released as a Korean song in their first Korean mini-album, "Bluetory".

Kim Hyun-joong: Kim Hyun-joong (; born June 6, 1986) is a South Korean actor and singer, and the leader and main rapper of boyband SS501.

Supporting paragraphs: Timing (EP) Kim Hyun-joong
Answer: SS501