D-Unit, a South Korean girl group formed in 2012 under D-Business Entertainment, debuted as a trio of Ram, UJin, and Zin with the single "I’m Missin’ You" and the album Welcome To Business on 2 August 2012; the group performed its first stage on M!Countdown the same day. In early 2013, the lineup expanded with guest member JNey, and the group released the digital single "Sleeping In (Part 2)" before launching its second studio album, Affirmative Chapter 1, on 4 March 2013, which featured collaborations with Zico of Block B and Vasco. Subsequent releases included the singles "Luv Me" (7 November 2012) and "Thank You" (16 April 2013). The group’s promotional activities encompassed a reality show titled Welcome to D‑Unit, a fan signing tour in Japan, and a performance in Vancouver for the 2K13 Feel Korea Festival in September 2013. Although D‑Unit did not achieve major chart-topping positions, it maintained a presence in the K‑pop scene through consistent releases and collaborations until the group’s activities ceased after 2013.
