My Mai Koakuma Na A Cup

Once again, the peaceful morning is shattered by a diatribe delivered by a sister to her brother. This is a daily occurrence at the Utsumi household, and the fact that his relationship with his step-sister, Miyu, isn’t improving is a cause of anguish for Mitsuru. While she may behave like an angel in the presence of their parents, when they are alone, she’s a pure devil.
One day, Mitsuru discovers that Miyu has a complex regarding her bust-size. He unwisely brings it up and she blows up at him.