Casey, who proved his potential as a vocalist by recording the top spot on the domestic mainstream music charts with Dream in January, returns to the public with his new song Let it rain in six months. In the meantime, Good Morning of Sums, My Way OST is singing and it is expanding Casey's musical spectrum through collaboration with various artists as well as a long run into a sound source chart.The title song Biyawara is an acoustic guitar based British pop genre that maximizes the feeling of the song with a variety of synth sounds. In the lyrics, I put a heart of a woman who pretends to be on the outside but can not forget a man who has left his heart.In composing, Cho Hyun Soo and Yu Ju Jin, the best hits composers in Korea, participated in the lyric song lyrics and Kim Na in the lyrics.Composed by Cho Young Soo, Yu JinLyrics by KiminaArranged by Young Soo Cho, Yu-JinChorus by KassyPiano by Cho Young SooEP by Ju-jinGuitar by SangwanRecorded by Yujin @ Nextar Studio \u002F Na Sumin @ MOJO StudioMixed by Choi Jae-young @ MOJO StudioMastered by Kwon Namwoo @ 821 Sound MasteringExecutive ProducerMusic Producer Cho Young SooManagement Director Shin Dong-gilArtist Management Park Geun-hong, Bin Seong-su, Cho Sang-gil, Choi Hae-min, Lee Young-young, Kim Young-hye,Planning & Marketing Kim Do Young, Huh Chae Won, Kim Eun Joo, Hwang Ju Yeon, Ham Ji EunAdministration Huh Chae Won, Kim Dong Jun, Choi Eun HeeVisual art reggae @ rodreamArtwork & Design Kim Hong, Kang Ji Yeon @ PINKKHair & Make-up Seowon, Hani @ ALUUStylist Kim Hye-miPhotographer New HallymMusic Video Lee Dong-duk, Park Jae-young, Lee Han-gyu, Cho Kyung-won @ Mustache Films