How about the presence of small horns on her head?

"This... This isn't what it looks like!"

"Really? It looks like you're getting buggered from behind in the shower."

"... Okay, so it's exactly as it looks like."

+1 Week... +1 Week... +1 Week...

(Cumulative Weeks: 44 Weeks and counting)

Maybe I've been watching too much Ghost in the Shell, but I imagined the Mistress being voiced by Melissa McGlynne.

Up for some recreational activity?

I don't know why, but she seems more objectified in this picture than when she's naked with the collar. Maybe it's the eyes?