In 2016, Mori won
Lead Japan Cup, becoming the youngest winner of the competition at age 12. She has repeated as the national lead champion in 2018, 2020, 2021, and 2022. Mori also won the Boulder Japan Cup in 2021 and finished second place in 2018. Mori made her senior international
competition climbing debut in 2019, winning two bronze medals in lead and one in bouldering
World Cups. In September 2022, Mori took first place at the
World Cup event in
Koper, Slovenia, finishing ahead of second-place finisher
Janja Garnbret, who had won all four lead World Cups of the season coming into Koper. Mori was competing in her first World Cup event of the year, and her first international event of any kind since
the 2020 Olympic qualifying event in 2019. She followed this up with first-place finishes in another two World Cups events, at the lead event in
Edinburgh, Scotland, and the season-ending combined boulder and lead event in
Morioka, Japan. In 2023, Mori competed in the
2023 IFSC Climbing World Championships and became the world champion in lead, becoming the first Japanese athlete to win a world title in the discipline. She also qualified for the
2024 Olympics by placing third in the combined event at the World Championships. In 2024, Mori finished in fourth place in the
combined event at the Olympics, expressing frustration for not being able to top the final route as previously promised to fellow climber
Akiyo Noguchi. On October 6, she won the silver medal at the last event of the
2024 IFSC Climbing World Cup, bringing her to third place in the year's ranking. ==Climbing style==