Dragon Crisis! (www-readlightnovel-me)

A normal high school boy Ryūji Kisaragi’s peaceful life is turned into an adventure by the return of his second cousin, Eriko. Ryūji and Eriko seize a relic box from a black market broker named FANG. In the box, they find a red dragon girl whom Ryūji names Rose because of her rose like pattern on her left hand. In ord…