Nagashi is the Japanese word for a kind of wandering minstrel (lit. flow-er/drifter). In their current form nagashi are closely linked to enka, a song style that developed in the early 20th century. Lately nagashi are rare but they may be spotted in the areas frequented by the older generation in Osaka, Tokyo and Kyoto, moving from bar to bar (usually singly) with their guitar taking requests for popular songs, particularly enka (hence the generational preference). They will either sing themselves or, more likely, play for customers who want to sing (they were a pre-cursor of karaoke). Formerly, nagashi were not the only wandering entertainers. Street musicians played enka for passers-by and storytellers with a picture box (often fixed to the back of a bicycle) told illustrated tales. Among the musicians were accordionists, and fiddle-singers playing 'violin-enka' well known for using their music as a medium for political subversion. Recordings of Japanese street performers are not very easy to find - the UK distributor Far Side have some.
Related post: Enka