Ruby's a Spy, Okay?!

is the third episode of the Sora to Umi no Aida anime.

Synopsis
Thanks to Haru's careless comment, the girls have to fight for the pool rights following the male's conditions. Furthermore, it is to Maiko's calculations that Haru, Namino, and Makiko make the balanced group that puts Namino and Haru on further bad terms. While Haru does her best to make up with Namino, they are somehow followed by a strange blonde girl.