I've still been exploring through the huge collection of one Naoko Kawai（河合奈保子）for the past few months and so I got to listen to Disc 3 which includes all of her non-single album tracks. And for a purveyor of the old kayo like me, this is a great way to encounter some of those hidden treasures that don't get to see the light of day via a BEST hits compilation.
Just my opinion here but although she may not have been the No. 1 aidoru in popularity back in the early 1980s (Seiko Matsuda/松田聖子 arguably took the crown there), I think Kawai had the best aidoru voice at that point. Clear and bright and cheerful, her golden tones seemed to radiate the sunny season simply from listening to the stereo. Perhaps audience members needed to wear sunglasses when attending one of her concerts.
The first track on that Disc 3 is "Bessekai" (Another World) which was originally from her 3rd original album, "Diary" (ダイアリー), released in August 1981. With Jun Sato's（佐藤準）melody skirting close to Resort Pop territory, Machiko Ryu（竜真知子）has Kawai trilling her words about enjoying fun and romance on a summer beach. Come to think of it, that boozy saxophone solo also had me thinking about some of that 50s sound that was going around in a number of tunes back in those days, aidoru or not.
Incidentally, "Diary" also had Kawai's 5th single, one of her trademark tunes, "Smile For Me" (スマイル・フォー・ミー), and that was also written by Ryu. That was the first time I heard of the singer via the 1981 Kohaku Utagassen, and that was where I said, "There goes an aidoru!"