[There's probably something wrong with him, if he thinks that Yurio's odd combination of reticence and defensiveness over his grandpa is a little endearing.]

Ah, he was there at the Rostelecom Cup, wasn't he? [It would explain how Yurio had gotten a hold of the katsudon piroshki in the first place.]

I think Viktor wants me to visit Russia with him sometime soon. Maybe I can meet your grandpa while I'm there.