What could i do?

I want to do something very submissive for my SO on Valentine's day. I want him to truly feel like he owns my body. I'm not sure what to do or how to start it. Also I'm new to this he isn't so I'm not sure what to do. What could I buy? Hes into EVERYTHING bdsm. Hes a total Dom, sadism, and he loves being called daddy and me his little girl/princess. I want to make this really special for both of us.