He sat there a moment longer while Souji had his way with his fork, and then put it back like there was nothing to it.

Clearly, he was being taunted.

Normally, he'd just leave the fork where it was and proclaim that he was full anyway. That was probably what Souji expected. But if Souji was going to do things to purposefully mess with him, he wasn't going to do what he expected. Instead of blustering or scolding or scowling, he just picked up the fork, and speared a chunk of pancake with it.

"Not with my hands."

And then he stuck it in his mouth. Indirect kiss that.