Ryuu no Hanayome Okotowari

In a town with a history of dragon legends, Sakura and Ren maintain peace as descendants with dragon blood and the ability to control water. Sakura frees Kouka, a sealed legendary dragon, to save Ren, who suffers from a weak heart. Kouka then inhabits Ren's body and compels Sakura to assist in awakening his full power. The story begins a fantasy centered on the forbidden bond between a girl and a dragon.