 On August 7, Zhang announced during a live Weibo interview that a new single will be released after promotions for "Agape"; the song and its music video will be a sequel to "Agape".On September 20, Zhang released her fourth single "Not Alone" in China through Baidu and then later released in South Korea through Korean music sites MelOn, Genie, Naver and Bugs on September 22.The single is a remake of Tiffany's "By Myself" from the SBS drama series "Ja Myung Go".