He could of course have responded to Optimus indignant reproach, but what was the point? The reaction itself confirmed at least part of his interpretation, and the pulse he got over their connection verified more of it, if only due to the lack of denial.

What was more curious was rather what came after that, the response to his stated intention. Megatron wasn't sure which parts of it caused what part of the tangle of emotion he recieved, but it didn't really matter. It made it obvious that. firstly, here there was something to work with, and secondly, that Optimus didn't truly disapprove.

Chuckling against the metal, he angled his helm to worry one of the support cables, biting down slightly too hard before turning back to Optimus throat again, simply pressing down in concert with pressing in with his finger.

He did it slowly to allow for the adjustment he hadn't given when he shoved his finger in, but inexorably, pressing as far as he could reach, wriggling his fingertip where the valve's delicate mechanisms pressed against it. He couldn't reach the actual floor of Optimus' valve with his finger, but he didn't really need to as the sensitive caliphers and tiny workings simply created a dense cluster to press against when it had nothing to push them apart.