Girl #10 Hirono Shimizu is a rebellious girl. In the manga and novel, the girl with spiked hair has been involved with prostitution and drugs. On the island, she is attacked by Kaori Minami, and it is briefly stopped by Shuya. In the novel, she shoots Kaori and runs away. In the manga, she expresses interest in his offer, but runs away after Kaori shoots her in the shoulder.
In the novel and manga, Hirono uses her entire water supply to treat her wounds. However, she suffers from septicemia, and becomes severely dehydrated. When she tries to get water from a well, she is attacked by Toshinori Oda. She shoots him and leaves him for dead. However, it is soon revealed that he is wearing a bulletproof vest, and gets up to attack her again. In the novel he strangles Hirono with a belt. In the manga Toshinori pushes Hirono her down the well, where she drowns during a final dream. Her body is later discovered by Hiroki who mourns her.