in april 2015, s.m. entertainment announced that a personal study had been established for lay's activities in china. in may 2015, he became a cast member of the chinese program "go fighting!" in june 2015, lay composed the song "promise" for the re-release of exo's second studio album, "love me right". he also wrote the lyrics for the chinese version of the song, while the korean version was co-written by chen and chanyeol.