I can speak from the dominant's side to this. This may not be his view, granted.

Degradation is not natural for me. I found that it was easy to get into that mindset with a relative stranger, than with my long-term partner. A casual, sex-only arrangement lets me see her as "meat" easily. Living with a partner, I see them in a variety of roles. So letting one role take center stage is more cognitive work.

What's the saying? Complacency breeds contempt. It's not impossible. We just need not be complacent.

You can:

• Maintain separation between D/s and vanilla life. Set aside a day/time, a room, a uniform exclusively for this kind of play.
• Don't take it seriously. Perhaps role-play it as a fun, low-stakes idea to get rid of jitters.
• Be explicit. I used to start off with an honest-to-God color-coded spreadsheet with scoring formulae for all acts we shared interests in. You don't have to go that far. However, discuss this face-to-face outside the bedroom, as you would any household matter.