Firstly, this video was originally uploaded by 第三倉庫 at this channel:
https://www.youtube.com/channel/UC67Hn3edghI1R0TLvRl839w
However, it was presented in the wrong aspect ratio. I have re-rendered the video in HD and presented it properly.
This is the breathtakingly beautiful Kaoru Yumi performing live during the 70s. I do not know what song she is singing.
Special thanks to 第三倉庫 for doing the heavy lifting. I do not know who the rights holders actually are, but 第三倉庫 is the source of the original video.
WACOCA: People, Life, Style.