Oyama began performing stand-up comedy at 17 years old. In 2012, she was a state finalist in the Class Clowns competition. That year she also performed at The Sydney Fringe as part of "Barely Legal - Australia's Best Young Comedians" alongside Neel Kolhatkar and Aaron Chen, and performed on Dan Ilic's FBi Radio show. Oyama became a writer for the children's sketch comedy show You're Skitting Me, and made her television debut performing stand-up comedy on SBS 2 in 2014. In 2017, Oyama was cast as executive assistant/receptionist Courtney Kano in the third, fourth, and fifth seasons of Utopia. In the same year, she joined the cast of ABC Comedy's topical entertainment show Tonightly with Tom Ballard as a writer; she also starred in the second and final series of the show in 2018.
