Shido held the Reiryoku of three Spirits within him, enough for her to be able to use the 12th bullet and still have some power left over to kill the First Spirit. To accomplish that, she required a significant amount of Reiryoku which she didn't possess, which is why she wanted to consume Shido. Here, she stated her real goal was to seek Shido out in order to be able to use her 12th bullet to travel 30 years back in time and kill the First Spirit. Later, it was revealed (at the end of Volume 4) that Kurumi had a conversation with a mysterious being that made it seemed like she was talking to herself.

Kurumi had claimed that it was because she simply wasn't prepared to face her, but later argued that she could defeat Kotori if she had more time stored up.

However, she was forced to retreat after being overwhelmed by Kotori Itsuka's destructive power. During the time Kurumi was a Raizen High School student, she almost succeeded in consuming Shido. Her purposes and reasons for moving were simple: consume Shido Itsuka, and in doing so, gain the Reiryoku sealed within his body.

Kurumi Tokisaki had used unstated and unexplained methods to personally transfer into Shido Itsuka's class so that she could get closer to him. As such, her title as the Worst Spirit comes from personally killing her victims with her own hands. She has killed over 10,000 people, with an estimate of only around 100 being Spacequake victims. Mana Takamiya reported that Kurumi Tokisaki is the most dangerous Spirit ever known.

Tokisaki kurumi wallpaper