Kunikuzushi is a humanoid puppet created by Raiden Ei (who he refers to as mother), but when she saw that her creation did not act the way she planned, she decided to move away from him, leaving him in a simple house where he is cared for by one of the helpers of her trust, who is a few years older than the puppet, Kunikuzushi's personality is the definition of a blank board, an innocent puppet, who knows few things about life, not even knowing the meaning of feelings like love.