However, her most immediately recognizable hit song, "シンデレラ・ハネムーン" — "Cinderella Honeymoon [jp]" (1978) has been such a consistent feature of monomane talent Korokke's routines, Hiromi Iwasaki has commented that when the intro played in concerts, fans would laugh, so she has ceremonially "gifted" that song to Korokke, whose performance has elongated both their careers.
Iwasaki made her official debut in April 1975 with the single "二重唱" — "Dyuetto", after winning a record contract on the popular Japanese talent competition show Star Tanjō!
[5] She continued to release big selling singles throughout the 1970s, and starred in her first rock opera, in the summer of 1979, as Ophelia in Shakespeares' Hamlet.
[5] In late '79 her single "Mangekyō", won her gold at the Japan Record Awards, as well as becoming the theme song for Subaru Leone.
[5] The single "Sumire Iro No Namida" won her the "Best vocal performance" at the Japan Record Awards of 1981.
[4][5] In the 1980s Iwasaki began focusing on musicals, and in 1987 played Fantine in the Japanese version of Les Misérables.