Ryota Kohama is the bassist of the Japanese rock band ONE OK ROCK. He was in the hip-hop group HEADS along with Toru Yamashita before they disbanded in 2002. In 2004, Toru and Ryota continued their activities as Ground 0. In 2005, he was invited by Toru to form a rock band, alongside their upperclassman Alex and Toru's friend, Koyanagi Yuu.
