Yusuke Aizawa (鮎澤悠介) (English name Ethan Aizawa), also known by his English stage name Eden Kai, was originally born in Hachioji, Tokyo, Japan on September 24, 1998, but moved with his family to Hawai'i, where he graduated at Henry J. Kaiser High School in May of 2016.

Aizawa was a child actor, but turned his focus to music, first playing in the brass band in middle school, but picked up the ukulele and the guitar, stating that he wanted to play an instrument that could more easily tell his emotions; he self-taught himself both instruments via YouTube.

He is most known for his appearance in Terrace House: Aloha State and was among the original housemates when the show began in 2016. He would again make a few appearances in Terrace House: Tokyo 2019-2020.

While he was still a high school student, he began releasing official music in 2015, which would include two acoustic instrumental albums; Touch the Sky (2015) and Feel the Earth (2016), but wouldn’t release his first track with lyrics until 2017, with the track “モノガタリ”, which is a song that he composed and wrote during his time on Terrace House: Aloha State.