Wanting more

I'm married. Have been for 10 years. However, we have decided several years back to be in an open marriage. We have been happy. Recently I have been wanting to get into another relationship. Just don't want to bring it up to my husband because it's with another guy. I have always been bi and when we agreed to the open it was agreed on with girls. We didn't discuss another guy. He said he didn't want another guy because he's straight. And I told him that was fine. I wasn't asking him to get another guy. But now after 7 years, I'm wanting another guy (not to be in a relationship with my husband). I know I need to talk to him. And I won't do anything without him knowing. That was why we agreed to this. It took the "cheating" out of the relationship. I know I don't fulfill all of his needs because it's not who I am. And he can't always fulfill all of my needs because of who he is. So we decided that we would find it in other people with conditions. We wouldn't do anything without the other knowing first. We wouldn't do one night stands. We also wouldn't force someone else on the other person. It had to be agreed upon by all parties. And lastly our marriage would always come first. At the end of the day it was mine and his relationship. Just feel like the bringinig it up the first time is always the hardest.