[Raising his brows as Yuuri figures out who he is. He reaches around to take his chin in hand, squishing his cheeks so he looks like a fish.] Oh ho~ Took you long enough.
[A glance at that sharp tone, a pause as if he's contemplating ignoring it, then seemingly backing off. Raising his hands in that universal sign of 'okay, I won't touch him'
And then, with a quick step and a swing with his left fist, he punches Yuuri in the stomach. Hard, but not nearly as hard as he could've. He pulled his punch but it would at least be enough to get the message across.
But just in case? He whispers into Yuuri's ear as he folds over his fist.] You touch him again I'll kill you.
[Then withdraws a few steps, on his toes in case there is any retaliation from either boy.]