Upon arriving to the island, the girls met two twin girls of the same age as them. Koharu is a flat chested tomboy with a bad attitude. While Chiharu is a big boobed, motherly girl. While Yuka, Rin, Natsumi and Saki bathed, they asked a wish to a small, round rock and Saki became invisible. Throughout episode 9 Saki and the girls continued pondering about her move to the island. At the end of the episode Saki seemed to have accepted moving to the island, and the girls have also befriended the twins.
This was an entertaining episode with some curious moments. Just as with the last episode of Natsuiro Kiseki, it was nice that the story moved to a different setting. Unfortunately, the series has reverted back to its character of silly drama and things working all out in the end somehow. The cliché personality of the twins did not help either. This episode gets a 7 out of 10.