So lost and confused

I seriously don't know what to do about my ex/baby daddy. He keeps saying he wants full custody or have my son 9 months out of the year. He told me he would sign away his rights then decided he wanted full custody. He raped me and multiple underage girls, hes a manipulative liar, a pathological liar, and an overall abuser. He met my son once when he was 2 months old but that stopped because i found out he raped a 14 year old girl.

I dont want child support. I dont want anything from him except him gone from our lives. He has only brought stress and pain and i dont know what to do