How do i bring it up to my husband?

recently while reading this app, I have noticed that i like parts of the daddy/little relationship and I have thought about bringing it up to my husband. the only thing I don't really want to do if refer to him as daddy, I understand it's different than like parent daddy but it's weird because we have 3 kids. I was just wondering how to go about it with him or if it's even worth doing it. we have a pretty good sex life and he takes such good care of me