Strange Dragon

Many years ago, a dragon descended from the sky to protect the country's king. Hibana, a princess, embarks on an adventure to search for the dragon. She saves a boy with a rare but real dragon scale. Does he know something...?

(Source: Chinatown KM)

Included one-shots:
Volume 1: Ryuuguu Fantasitca (Dragon Castle Fantastica), Hyouketsu Kismet