Beginning as a short sprinter as early as 2014, Kuboyama won the 2018 Japanese University Championships in the 100 metres, running 11.86 into a -2.1 m/s headwind.[1] At her first Japanese Athletics Championships in 2019, she contested the 100 m and 200 m but did not advance to the finals. She also failed to advance to the 100 m finals at the 2020 Japanese Athletics Championships.[1]
In April 2024, it was revealed that 2023 Asian Championships 400 m silver medallist Fairda Soliyeva of Uzbekistan failed a test for meldonium, disqualifying her and promoting Kuboyama to the bronze medal.[6]