When he was elected at the age of 23, he was the second youngest-ever member of the state House of Representatives after Tulsi Gabbard.

[2] A fourth-generation Japanese-American,[3] Sayama attended the Punahou School, graduating in 2015.

[4] Sayama attended New York University Shanghai, graduating in 2019 with a degree in Chinese Global Studies.

[5] He is currently attending the University of Hawaiʻi, where he intends to get a Master of Public Administration degree.

[6] He won a seat to the Hawaii House of Representatives after longtime incumbent Democrat Calvin Say retired to run for Honolulu City Council.