^ It's tufts of hair that happens to look like like ears. (how much vary a bit depending on the picture).
by the way the dark-skinned tomboy is Mitsuki and her white-haired girlfriend is Natalia.
^ Lol If that ever happen, the rest of the Anime community already hated Yuri because of Citrus, we will watch this one finish the job and kill Yuri's reputation forever