Kagura wants nothing more in life than to escape from Naraku's grasp, but unfortunately he has removed her heart from her body, making it impossible to leave. He often threatens Kagura with this fact, or even squeezes it to show her what pain truly is. He tries to tell her that he has done her a favor by removing her heart, making it so that her body can heal itself without much pain. However, the real reason it is removed is so that she can't escape from his grasp. Kagura resents Naraku for this, causing her to look for someone else to help her destroy Naraku in order to get her heart back.
Tomorrow is a new moon. Even the moon has days when it can hide in darkness... but with Naraku holding onto my heart, there's nowhere for me to run
Kanna tries to tell Kagura that they are just tools to Naraku, and not seen as life. He gets to decide their fate and when they can live or die. Kagura tries to run away multiple times when Naraku's barrier is weak, but she always has to come back because he has a hold of her heart.

Because Kagura doesn't have a heart, and because she is an incarnation, or an attachment of Naraku, she follows similar traits of Kagura. Kagura becomes very selfish when she realizes that she needs freedom. She starts acting out and doing things for her own good instead of thinking about others. She is even quoted in episode 167 to saying, "I value my life too... so I'm going to use you guys. Hah! After all, that's Naraku's specialty." Her life is the one thing she knows how to protect, and even at that, its a slippery slope because she is uncertain if she will be able to prevail in the end or not. Because of things, I find it kind of ironic that she hates Naraku but uses him as an excuse for her actions. I believe that this shows that she is controlled by him even more than she thinks she is because she literally is part of his flesh.

Kagura shows a soft side as well. She won't hurt people more than she has to to get her way. She never harms Kohaku or Rin when they are in her presence either. Once she 100% realizes that she wants Naraku dead, she even gives hints and clues to InuYasha and his gang where to go so that they can hopefully kill Naraku. Although this can be seen as just being nice to get what she wants, she could easily have hurt them or been nasty, but she isn't. She only gets mean when she sees Naraku's insects following her around because she knows she has to act a certain way in order to not be suspicious to Naraku.

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