Рэй Куроки

Akane's mysterious classmate. Prefers to remain aloof, always choosing to be alone. Lives in a sparsely furnished apartment with a parrot named Bisk. Constantly wears a scarf that covers a feather tattoo. Unlike the main heroines, she has the ability to enhance the power of "loners" by shooting them with a bow. She serves as an intermediary between those who control the "loners" and the Crow. It is later revealed that Rei is from another world, which can only be accessed with a special key. One day, upon opening the door to her world, she finds it crumbling, and her parents, standing behind the bright flames, cry out for her to run back. The Crow tells Kuroki that the "Engine of Incarnation" and the people are to blame for everything. Therefore, Rei decides to seek revenge and help the "loners" destroy the human world.