Tsuki ni Murakumo, Hana ni Arashi

Hikaru and Ryuu were classmates in art college and have been friends for twelve years now... But, ever since winter ten years ago, Ryuu's confessed his love for Hikaru multiple times. Each time, Hikaru's managed to dodge giving him an answer, and they've continued to be good friends, but when Ryuu, who's an artist now, is dodged for the tenth time, he pushes Hikaru away by saying not to come back if they're just friends! This is an elegant, pure love story spanning ten years between two guys in their thirties. One is an elite artist who lives in his own world, and the other's a ditzy guy from a rich family in Kyoto!

(Source: Renta!)