She won the overall 2019 World Cup title in competition lead climbing in her senior debut season.

In 2018, aged 14, Seo redpointed the 9a (5.14d) graded sport climbing route, Bad Girls Club, at the Wicked Cave, near Rifle, Colorado.

[11] In August 2021, aged 17, Seo competed in the 2020 Summer Olympics and finished in eighth place overall in the women's combined event.

[15] She also represented South Korea at the 2022 Asian Games where she received the silver medal in the women's combined competition.

In August 2024, she made her second consecutive Olympic Games appearance and finished in sixth place overall in the newly reformatted women's combined event.