All around the world, Riyou (日友 
, Riyou 
, 日有 ) is quite a rare primarily masculine, but scarcely feminine first name. The first name Riyou is characteristic of Algeria, where it is a very rare male name, China, where it is a very rare primarily boy's, but very seldom female name, and India, where it is an extremely rare feminine name. Much less frequently, Riyou is the last name as well as the forename.