Kiru is a Shoot'em up Bullet Hell about Alice's story. Alice wakes up on top of a tower, with no memories, looking out the window she is shocked by the landscape, huge mansions, Gears (ships) flying in the streets and people walking on bridges between buildings. With her sword in hand she jumps from the tower and flies looking for a course. She encounters a mysterious girl who tries to kill her for no apparent reason, but during the fight Alice manages to successfully deliver a blow and regains part of her memories in the process. Alice then decides to go on a journey to understand more about the world she is in and her memories.