Nope, zero objections. Tony was easy like that -- he knew it was all in good fun rather than a need to actually be weird and controlling about things (which would have been, for the record, very not sexy and very not fun). And Tony? Well. He liked a good time.
And he liked it when things got a little rough. Hell, he was only human.
He gripped the sink and sort of just arched his back so that his ass was up against Steve's front. "Oh," he said, not really in surprise so much as dark, keen, interest. "Well. That's very thoughtful of you."