She considered auditioning for the first Keyakizaka46 audition, but ultimately thought it was impossible for her to pass. She regretted not auditioning soon after. Later, she learned about the Hiragana Keyakizaka46 audition while watching Keyakitte, Kakenai? and signed up
She kept her application a secret from her parents, who were against pursuing jobs in the entertainment industry. When she progressed to the third round and began streaming on SHOWROOM as part of the audition process, she told her parents. Her mother was furious, but her father encouraged her. Now both of her parents support her activities
Shares a family name with Sasaki Mirei. Their nicknames are therefore similar (Sasaku and Sasami). On many Hinatazaka46 programs where they both appear, they're referred to by first name only ("Kumi" and "Mirei") whilst other members go by family names
Can play trumpet. Performed Whiteberry's "Summer Festival" on trumpet on Keyakitte, Kakenai?
Did brass band club activities all the way through high school