Claws pick their way across the table between them, casual, as Percy is distracted going on about the subject. It was a slow careful crawl, until the edges of his pointed digits find Percy's and their fingers twine. For a little while that's how it remains, Thundercracker jotting notes down with the opposing hand and still paying attention, just doing so with the added bonus of their contact.
Until the hand holding includes the gentle brush of the seeker's thumb over his knuckles, the delicate squeeze of their twined fingers, the casual affection in his gaze.
At a point, when Percy takes a pause, TC lifts their hands, turns them so the backs face one another and leans to press a kiss, all too adoring to the back of the scientist's hand. Lingering in that intimacy, as if reluctant to pull away. But when he does, there's a smile in place there, lowering their hands back to the table surface. "Sorry. Couldn't help myself."
Initially, Perceptor is able to casually ignore Thundercracker's hand finding his own. His explanation of alpha decay in particle physics keeping his attention swayed. He's talking about how the phenomena is only present in heavier nuclides when TC's fingers interlock with his. Whatever sensors in his fingertips actively dulled so as not to be too distracted by his partner's spark pulse. And, for the most part, it stays that way.
He's about to move on to which elements in particular are most affected by alpha decay when TC rubs a thumb over his knuckles, then lifts his hand to his lips and— Well he's glad he was in between subjects. Otherwise he certainly would have stuttered.
Dulled sensors come to life and he feels the grain of Thundercracker's alloys. The subtlest of differences. Many do not realize, he thinks, that a Cybertronian's hand contains microscopic differences to anyone else. He has felt no two alike. He thinks he is close to memorizing the particular patterns Thundercracker's hands have.
Then there is the intimacy of feeling the electrical signals just beneath, the rhythm of his spark felt all the way in his claw tips.
There is no restrictions in the way Perceptor's face opens up, how it softens, then turns to mutual adoration. He does not normally allow himself to... feel like this. As intensely. There is a spark of who he was before his reformatting in his eye as he stares.
" It's um— " he stammers anyways, " it's fine. I-I don't mind. I um... I... cherish it when you do that. " He looks bashful now, ducking his head just a little. He feels he owes some sort of explanation: " I was meant for metallurgy microscopy. My tactile sensors upon my fingertips are more sensitive than the average Cybertronian. "
His smiles soft, despite his earlier shyness. " I can tell. Your spark pulse. I can feel it. The alloys that make up your hand. The grains in which ways it formed. The electrical pulses beneath. It is... a lot of information to process. But not unpleasant. "
