Ryuu no Eigakan 

In a little mysterious world where dragon people that sometimes transform into dragons live together with humans, a boy's childhood dragon girl friend is supposed to move to the dragon's city when she turns 17... This is a heartwarming love story between a dragon and a human! (Source: Shonen Jump Plus, translated) Note: This is the result of a contest where people could submit manga storyboards made with Jump's World Maker app, with the winners getting their idea professionally illustrated.