Description:

When she was little, Mira Kinohata met a boy named Ao at a campsite in town. While gazing at the starry sky together, Mira learns that there's a star with the same name as herself, but no star named Ao. The two then promised to one day explore asteroids together and find a star to name it after him. Several years later, Mira enrolls at the Hoshizaki high school and decides to join the astronomy club to fulfill her promise. However, she learns that the astronomy club will be merged with the geological research society to form the earth science club. Reluctantly, Mira goes to the club room and is reunited with Ao Manaka—the person she made the promise to explore asteroids with—and is shocked to learn that she is a girl! (Source: MAL News)

Description:

The enormous cave system, known as the Abyss, is the only unexplored place in the world. Nobody knows how deep down goes this titanic pit, inhabited by strange and wondrous creatures and full of mysterious ancient relics which purpose in unknown to modern man. Generations of bold adventurers have been drawn by the cryptic depths of the Abyss. In course of time those bold enough to explore the dangerous pit came to be known as "Cave Raiders." In Oosu, the town at the edge of the Abyss, there lives a little orphan named Rico, who dreams of becoming as great a cave raider as her mother was and solving the great mystery of the pit. One day exploring the murky depths she stumbles upon a little boy, who turns out to be a robot...