Called an inner snake. I have heard this voice called an inner demon or dragon. An inner monster. I often call mine inner darkness or inner shadow.
But today I told this part of me, "Thank you for all the lessons. Thank you for showing me what was hidden in myself and what needed to come into the light. Thank you for helping me to know myself better. I don't hate you. I will not try to destroy you or remove you. I accept you with love and I am grateful you exist."
I don't expect this voice or part of me to go away, but I will show this part of me gratitude, love, and compassion.