I plan on cheating on my so.
Can you let me know why you would do something like that to your SO?
He just isn't very romantic towards me anymore. He is no longer very fun to be with.
Even if you don't enjoy being with him anymore you shouldn't cheat on him. Break up with him then find someone new.
When he cheats on me with someone else then, we'll be even.
You are better off just breaking up. If you continue to play games with one another and cheat on one another you will only cause resentment. You guys should either try and talk to resolve your issues, or separate.