year, she released her debut EP entitled Full Moon. On July 23, 2014, it was announced that Yeeun would be making her debut as solo artist under the pseudonym Ha:tfelt (amalgamation of the pronunciation of the word "Hot" and "Heartfelt"). Her debut mini-album Me? was released on July 31, 2014. 2015: Line-up changes and comeback with Reboot On June 24, 2015, JYP Entertainment announced that the Wonder Girls would be making a comeback after a three-year hiatus. A representative of the agency confirmed that former member Sunmi would re-join the group for the first time since withdrawing in 2010. Rather than a dance group, the Wonder Girls returned as a four-member band with each member playing an instrument: Yubin (drums), Yeeun (keyboard), Hyerim (guitar), and Sunmi (bass). Their comeback featured a retro, 1980s sound resonant throughout the album, similar to some of their past releases. On August 2, "I Feel You", the lead single from album, was released. The group released the album, titled Reboot on August 3. The album was a commercial success, charting number five on Gaon Albums Chart and number two on Billboard World Albums. Each member participated in the composition and production of the album. On October 2, it was announced that the Wonder Girls would host an episode of Saturday Night Live Korea. They performed their hits "I Feel You", "Nobody", and "Tell Me". On December 27, they performed at SBS Gayo Daejeon, and on December 31 at 2015 MBC Gayo Daejejeon. Reboot was ranked No. 1 on The 10 Best K-Pop Albums of 2015 by Billboard, and also No. 18 on The 20 Best Albums of 2015 by FuseTV. 2016–17: Why So Lonely and disbandment In mid-2016, the group started promoting their upcoming single. On June 18, they released one of its B-sides, titled "To the Beautiful You". On July 5, the Wonder Girls released the song "Why So Lonely", with "To the Beautiful You" and "Sweet & Easy" serving as B-sides, as a CD and as a digital single. The single was commercially successful in South Korea—the digital download topped the Gaon Digital Chart. On July 12, the group performed the dance version of Why So Lonely for the first time on SBS MTV's The Show, winning the trophy for that week. This was their first win on a music program since the release of "Like This" in 2012. The group also performed