Is it normal to want sex with two men at once?

Ok. My boyfriend is open to an open relationship. There is a different guy that I was with before my boyfriend. We still talk and still want to have sex. My boyfriend says it's ok. He says he will leave so I can have him here. He also says if I want both of them simultaneously he is open to that.

I don't know whether to enjoy this opportunity - basically having my cake and eating it too - or whether to not do it and be saddened by the fact that they are both ok with this arrangement.

I want to do it - physically, but emotionally it feels wrong. Like I should not want to do it and I'm a bad person for wanting it. I also feel like somehow I'll get punished.

Would you do it? Opinions? Is this normal?