The photo is from an old album that my husband Takashi bought in 2012/13. Some photos in the album are dated 1934 but we think this photo is earlier - probably 1920's. The album has photos from Kurashiki and the Seto Inland Sea so it might be from Okayama - we don't know.
One of the comments on Reddit questions the authenticity of the photo based on both its quality and the hairstyles. I can assure that person that both the photo and the hairstyles are 100% authentic. If you look at my original post there is photo from another album of a fairly conservative looking young man with a similar style:
This was an exciting time of 'Taisho Democracy' liberalism when relatively wealthy mobo ('modern boys') and moga ('modern girls') set the fashion. Here's some more 'old school cool' from the same album - most of the photos in the album are a bit more conservative than this:
As some also commented on Reddit, the world would have soon changed dramatically for these young men and there's every chance they didn't survive beyond 1945.