<human>: Can you condense the text into a few key points?

My boyfriend (26/M) of 2 months and I (22/F) were at my house last night, watching Netflix and discussing the show Orange is the New Black. The main character, Piper, is in prison and cheats on her fiancee with another inmate. He made the comment that if I were Piper and cheated on him, I wouldn't make it out of prison alive. He says it was a joke but I'm feeling unhinged by it. He thinks I'm being sensitive and says he would never hurt me physically. The fact that he would even think violence against me is laughing matter is really hurtful. He's been cheated on before so I understand his fear of it repeating, especially with the stereotypes about bisexuals that exist (I am openly bisexual and have been open about it with him from the start). Am I overreacting? Or should I see this as a red flag? I'm a late bloomer and this is my first, real relationship so I'm at a loss.
<bot>: Boyfriend joked about my death if I were to cheat on him. I don't know if I should just break up with him now.