Heard this one on a recent "Uta Kon" (due to NHK going long on its newscast, last night's episode was summarily canceled for the TV audience at least) where a movie scene of Yujiro Ishihara and Ruriko Asaoka（石原裕次郎・浅丘ルリ子）were walking pensively at a harbour.
The movie in question was "Yuuhi no Oka" (Sunset Hill) from 1964 and although the J-Wiki article on the film didn't expressly mention it, it was most likely based on the duet between Ishihara and Asaoka released in September 1963. Hit songs often got made into movies back then in Japan.
What struck me about the song "Yuuhi no Oka" (and according to a lot of the travel articles I've translated over the past few months, the Japanese do love their observation points looking toward the setting sun) was that it was an Ishihara song that was closer to the enka/general kayo side of things rather than the Mood Kayo I've usually associated Tough Guy with. And it's rather mournful as well; although I couldn't get a complete understanding of the lyrics by Shiro Hagiwara（萩原四朗）, the feeling is that the protagonist is heading to the titular hill to try to forget the end of a love affair. It's been quite the enka trope for folks to head way out of the city to purge themselves of the sad feelings once a romance is done.
Kenroku Uehara（上原賢六）took care of the music which sounds like something that an old-fashioned balladeer would have played on his guitar or accordion as he walked through the side streets of downtown Tokyo back in the postwar era. Again, there is a certain dirge-like quality to it which could have gotten the drinkers inside to get a little more introspective about life.
The video directly above the previous paragraph looks like one open karaoke session with Ishihara and Asaoka doing the performance. Asaoka appears somewhat embarrassed while what looks like the Japanese version of the kayo Rat Pack patiently listens to the duo before getting its chance at the microphone. It must be quite the thing to see this sort of old coverage for kayo fans.