Curious but super cautious???

So basically keeping this super short and to the point, I brought up a hypothetical idea to my husband about me having a "girlfriend" just to kinda feel him out about it. I'm curious as to what it would be like to be with a girl and surprisingly, he's totally understanding about it. He was super supportive which is great! However, at the same time even with his support I almost feel wrong about it. He gave me boundaries which is totally cool with me, I just feel like it's almost the same thing as stepping out of our marriage even with him supporting it.?

Also, the girl I mentioned to him as a hypothetical situation I know that she is interested in me as well. He knows this too, but we all three work together. He's also fine with this but I guess I'm just super cautious about it all because of that and I just feel like I would feel like it's wrong even though he says hes totally okay about it.. Advice??