Midori no Yashiro no Ryuujin-sama

Midori, the daughter of a shrine owner, summons the dragon god to help the spirit of a girl who appears by a nearby river. The dragon god is curious about the present world and is friendly towards the selfless Midori. However, he has difficulty granting the girl's wish to "see her sister." Will the strange buddy of Midori and the dragon god be able to help the spirit?