About that I am not sure I agree. For sure all of us have both good and evil inside of us, many philosophers argue that embracing ones dark side is crucial for psychological well-being and emotional regulation, from my own experience it seems the more one is willing to acknowledge and accept the darkness within oneself, the less power over you it will have, or rather the more you'll be able to control it constructively.Well that seems to be the Gnostic view and is ironically what many in the Occult also believe. However just because both are necessary, it doesnt mean that you don't have to take a side or that you can welcome both into your life. A house divided cannot stand.
As regards "demons", when evil forces residing in you become directed at yourself and produce mental anguish, as we're discussing can occur with Kundalini, perhaps one should not view it negatively. Rather it may be a sign that ones consciousness has become stagnant and is yearning to be reborn, that these demons serve your consciousness a purpose to destroy its outdated beliefs and values so it can become free to evolve into something new.
I may have read too much Jordan Peterson lately...