When it comes to the 70s duo Pink Lady, I'm always going to envision Mie and Kei as the high-energy pair wearing the snazzy get-ups and high-kicking choreography. It's hard for me to imagine the ladies as anyone otherwise. And yet, like anything else, all things had to come to an end and Pink Lady did so in 1981. However, although the entertainment entity known as Pink Lady was no more (at least, for several years), the women themselves continued with their own individual careers for sometime afterwards.
Mitsuyo Nemoto（根本美鶴代）stayed with her stage name of Mie（未唯mie）whereas Kei was now Keiko Masuda（増田けい子）, and it didn't take too too long for either of them to get their first solo singles out. Less than 6 months after Pink Lady broke up in March 1981, Masuda released her debut single in November, "Suzume" (Sparrow) which was written and composed by Miyuki Nakajima（中島みゆき）. According to J-Wiki's article on the song, when Pink Lady had watched Junko Sakurada（桜田淳子）perform "Shiawase Shibai" (also created by Nakajima) on a music show that they had both appeared on, Masuda remarked admiringly that she had always wanted to sing such a mature song.
Well, go ahead a few years later, and Masuda was now on the music shows by herself, sans sparkly outfit and sans frenetic dancing. She debuted as a solo act with a dramatically more melancholy ballad about a relationship that only seemed happy on the outside. I can't say her singing was the most polished but it did perhaps reflect the fragile state of the heroine in the unhappy affair.
"Suzume" broke the Top 10 by peaking at No. 9 and later becoming the 47th-ranked single for 1982. It was the most successful of Masuda's 10 singles, selling a little over 250,000 records. It was also a track on her debut album, "Hitori ga Suki"（ひとりが好き...I Like Being Alone）.