Мидзухо Косака

Kosaka Mizuho is a student at Saint Lucia Academy. She first appears in Utsutsukowashi-hen. One day, she sees a teacher in a swimming pool dead. A lot of the students in her class says that she is always alone and doesn't open up to anybody. Yukari, the class rep, always seems to bully her like in the first chapter she takes her notebook, only to have Sonozaki Shion steal it and give it back to Mizuho. She later develops a friendship with Shion. It is revealed in Chapter 3 of Utsutsukowashi-hen that she was about to be killed by her grandmother when she was very young, just like Shion. Mizuho is somewhat similar to Ange Ushiromiya from 'Umineko No Naku Koro Ni'. They both are loners at the St. Lucia Academy and are carrying mysterious notebooks around. They both are always bullied by their classmates, especially the class representatives, and told that their bad marks lower the average grade of the class. In addition, past of the both girls is wrapped in mystery and involves some mysterious tragedy happened to their families.