I personally consider it to be more sexual.

For me there is general submission to my Master and sexual submission to him as well. I think sexually submitting to someone adds another level to it for me than just having normal vanilla sex.

I think there are more things you can do in a D/s relationship than you can in a vanilla relationship that can be interpreted as sexual. We all have fetishes, for example. There are those of us who get off on pain or causing pain which in a general sense isn't a component or a very big component in a vanilla relationship. Humilation isn't generally a component in a vanilla relationship either yet I know many who get off on it. This for me, makes it more sexual.

So, I think considering how many different things can be interpreted as sexual by the people who practice those things in the realm of BDSM that it is more sexual, atleast for me. see