Suneohair was celebrate the 20th anniversary of their major debut in May 2022. Since he turned 51 that same May, he created a song to commemorate the 20th anniversary, using it as the theme for 5120. To commemorate the 100th live streaming live "Hello from Taira no Oyama" that started during the coronavirus pandemic, flat mountain records has decided to release the live streaming live! A song that traces the trajectory from the CD debut with a major record company until now. (Taira no Oyama = Japanese mean is flat mountain)