Amamiya Shizuku♀

The protagonist's younger stepsister. When she was little, her father remarried and she had a hard time accepting Makoto as her older brother. She still doesn't talk to him much, but when she has spare time she'll go to his room and read magazines on his bed. She sleeps a lot, and always has to be woken up in the morning by her brother. She even says herself that she can't do anything without him.

She rents a lot of horror movies from the store that Makoto works at, but since she's a scaredy-cat, she can't watch them unless he's with her.