According to the J-Wiki, this was Kyoko Koizumi's（小泉今日子）declaration tune as to her status in the music industry, and it was suitably brash and sassy, just like her image. Apparently in the beginning, her 17th single needed a title, and so a public contest was held in which people could give in their ideas for a name. 174,000 samples of correspondence flooded in. Ultimately, an economist by the name of Kazuhiro Ohnishi just put together the expressions "nantettatte" and "aidoru"together and sent the suggestion in. A song was born. Also, the song was written by Yasushi Akimoto（秋元康）of Onyanko Club and AKB 48 fame, and composed by veteran Kyohei Tsutsumi（筒美京平）.
"Nantettatte Aidoru" hit the top spot on Oricon right from its release in November 1985 and became the 21st-ranked song of 1986. The strong impression of the song earned Koizumi a quick ticket to her 2nd appearance on the 1985 Kohaku Utagassen, just 5 weeks after the song's release. 420,000 copies were sold.
The single is also available as a track on her 8th album, "Kyoko no Kiyoku, Tanoshiku, Utsukushiku"(今日子の清く楽しく美しく...Kyoko's Pure, Enjoyable, Beautiful).