Ichijo's Sister

Ichijos younger sister is just as mysterious and relies on drawing on a sketchpad to communicate as she is too young to converse. She is the only other one aside from Ichijo who is aware of the aliens keeping watch over Becky. In episode 7 she has a large role when she comes to school and causes some trouble. She appears regularly after this including episode 15 and is the bringer of the disease from the alien spaceship which affects the class in episode 19.