If Saori had her way, her big sister Iori would always be there beside her--just reach out a hand and they could touch, open a mouth and they could talk. But now Iori has a girlfriend. And a job. And a lot less time for her little sis. Somehow, whenever she can't be with her sister, Saori finds her way to her classmate Shizuku. But what exactly is that girl to her...?