Please Twins!

Synopsis

The three were drawn together by a photograph of their childhood home which later makes all of them seek out the house in the picture. However, the picture shows only two children, a boy, and a girl. The three conclude from this that only one of the girls, either Karen or Miina, can be related to Maiku. The other must be a non-relative. The only other identifying feature of the pair in the picture is that the boy and the girl have eyes of the same unusual color, a feature that furthers the ambiguity as all three of them share the same eye color.