Domination and submission fantasies in the bedroom

Hi, my wife and I are both Christian and recently married and over the course of our relationship, I discovered that my wife enjoys playing a submissive role in bed and wants me to be dominant.

I want to stress that she is certainly not a pushover in her normal life as she is quite successful in a high-stress career and clearly has thoughts and opinions of her own. However, when it comes to the bedroom, she loves being dominated and told what to do. In particular, she:

• likes being called "pet" or "kitten" or "maid" or "good girl"
• likes to call me "master" or "sir" or "mister <my first name>"
• would never want to be called or call me such names in normal life but ONLY in the bedroom when she is in the mood.
• doesn't like profanity use

Furthermore, as the most powerful sexual organ is the mind, she likes it when we engage in certain fantasies or role play (for example: I am a powerful baron and she is a maid for hire who is slowly taken advantage of)

My question is: Is this something that is okay to explore as a married couple or is this considered sin? Would this be acceptable since it is consensual and we are growing in marital sexual intimacy with each other and learning to love and enjoy each other more?