Young Nae is ostracized for constantly talking to herself; in reality, she is conversing with a bizarre creature visible only to her. After her beloved grandfather dies in a tragic car accident, Nae senses a spectral force at work, leading her to cause a disturbance at her kindergarten. Under these circumstances, a specialist is summoned to assess the situation: Hiromasa "Nine" Tsukumo, an eccentric individual accompanied by his own abnormal companion. Nine quickly explains the true nature of their special friends to Nae and resolves to help hunt down her grandfather's murderer.