This is the element of the equation that makes this shitty to do. Additionally, you're only thinking about this from a fairy tale standpoint, not reality.
Cheating has many forms, but if you have to do something like this that relates to something you find sexually appealing behind your partner's back, then what does that say about the relationship you and them?
I find your viewpoint to be so self-centered that I don't think you even understand what it's like to have someone in your life that matters right by your side. If you do, with this viewpoint on the issue you really don't deserve it, since you're probably the type that does whatever he wants whenever he wants, no matter what is going on in your life.
This viewpoint actually disgusts me and makes me frustrated because of how selfish it is, and because of how I don't see a happy ending in any capacity. Do what you want, but don't condone someone cheating on someone they care about.