Do I need to tell my boyfriend about my dad?

I was raised by my grandparents on my mom's side of the family. My dad left when I was young and then my mom lost custody of me for neglect and never tried to get me back. While I've seen my mom a few times I've never really met my dad. I know my dad has done some awful things which is why I've chosen not to reach out. When I was 13 I found out he had gotten himself arrested for CSA. He assaulted a 14 year old boy and the details are.... Horrible. He assaulted this child on multiple different accounts and would drug this boy and assault him with objects. It was terrible. My dad pled guilty got 10 years, served 6. He tried to have a relationship with me but I blocked him. Especially since my dad believes he was the victim in the situation and what he did wasn't wrong. If I ever have children I don't want them around him.

Where my boyfriend comes in is we have been together for over a year and are talking about marriage. He opened up to me about something traumatic happening to him as a child said he was raped. I comforted him and thanked him for telling me. When he told me the guys name.... I asked if he had a mug shot and my boyfriend at first didn't want to even see his face because he hates that man but did decide to show me.... That's my biological dad... I never talk to my boyfriend about my parents because I call my grandparents mom and dad. He knows my dad went to prison but not details. Now I feel like I have an obligation to tell him but he hates my dad. My dad is the man that ruined his life and traumatized him. What if he can't separate me from my dad and I lose him. I'm son conflicted 🥺🥺😞😞