Walking down some of those side streets in the shitamachi area of Tokyo definitely brings in those old-fashioned arrangements of enka or Mood Kayo. Although I know it's already Saturday afternoon over in Japan as I type this, the Friday night probably had the usual uptick in drinking activity on those very streets.
I'm kind of surprised that I hadn't discovered this song earlier by the silky-voiced Yukari Ito（伊東ゆかり）but it took one of those old retrospective videos on "Uta Kon" (うたコン) recently to let me know about "Koi no Shizuku" (Tears of Love). Released in January 1968, I could identify with the melody by Masaaki Hirao（平尾昌晃）as being a Mood Kayo not about drinking but about walking as a couple through those lantern-lit streets that I was talking about above, whether they be in Asakusa or Akasaka.
And man, is it ever drenched in Mood Kayo music! Lovely shimmering strings and that Latin guitar really do sound enticing enough for that couple to come in out of the rain for a bit of a drink. Unfortunately, Kazumi Yasui's（安井かずみ）lyrics make it pretty sure that any further joint drinking activities and other joint sessions are most likely over for the two. There is a lot of mention of the titular lachrymal fluid soaking into the guy's shoulder or being dappled onto his cheek. I had been hoping it was only because the lass was so happy in love. However, there was that one line where Ito sings about her hoping to forget what the guy had just said. I don't really take that as good news and besides, when it comes to the old kayo, the songwriters do love to use that "Parting is such sweet sorrow" phrase to heart.
Ito scored a No. 1 ranking on Oricon for "Koi no Shizuku". In fact, according to J-Wiki, the song provided the first time that a No. 1 ranking was given to a female artist since the Oricon charts began in November 1967. To give further glory, the song stayed at No. 1 for 4 weeks in a row and then after being dethroned for a few weeks, it was back on top for one more week. By the end of the year, "Koi no Shizuku" was the 5th-ranked single of 1968. Oricon may have been new but NHK's Kohaku Utagassen had already been well established; Ito was able to come onto the program for a 6th consecutive time based on the strength of this one song. It and "Koyubi no Omoide"（小指の思い出）are considered to be Ito's trademark tunes.
For such a song, cover versions are inevitable and there was one by Michiko Maki（牧美智子）. Her version was included in her 1974 debut album, and it has a slight bit of 70s disco to it while Maki's higher vocals provide less world-weariness and more innocence.
And here is Hiroshi Itsuki（五木ひろし）serenading the singer herself with her own song!