Women seek to please men they perceive as alpha. They want to satisfy you because they know that it is the best way to keep you around. They will be willing to do things they don't enjoy, just to make you feel good, like anal.

You should reward their submission by showing your pleasure. Be loud when you cum. Make it obvious that she helped you get what you wanted. She is looking for a reaction, so be reactive.

Like all rewards in classical conditioning, it is better to give them intermittently, never be predictable or she will become complacent. Also, don't overthink it, do what comes naturally and makes you feel good.