Kurumi is a person whose personality is hard to read. She possesses a dislike of humanity that borders on mistrust, which is something that she shares with most of the other Spirits in their debut. She is a skilled actress, capable of putting on the façade of an innocent, curious young girl when she needs to, which is shown when she registered as a student at the Raizen High School, and speaks in a polite manner. However, under that mask lies a psychotic woman, prone to fits of insane laughter and possessing no regard for human life, regarding them as a food source to restore her own time, and thus, a disposable commodity.
There is a twisted justice behind her methods however, as the people that she brutally murdered were would-be rapists and animal abusers. In addition, a good sign of her sense of justice lies in her ultimate objective: to go back in time, kill the First Spirit, and prevent the spacequakes from ever happening and saving millions of lives in the process. This goal made Phantom call her a kind person, albeit sarcastically.