地球最後の告白を (Chikyuu Saigo no Kokuhaku wo)

Background
This song was uploaded onto Nico Nico Douga on June 26, 2012. It is one of Kemu's most popular songs and has reached over 1,000,000 views. This song is featured on the album IA THE WORLD ～光～ with IA as the singer instead of Gumi.