[1] Iwai was born in Saitama Prefecture and started playing golf at 8 years old.

[1] She won the Golf Digest Japan Junior Cup twice.

[2] Iwai turned professional and joined the LPGA of Japan Tour in 2021.

As a rookie she won a title on the developmental circuit, the Step-Up tour.

[5] Her twin sister, Akie is also a professional golfer on the LPGA of Japan Tour.