Hm, the grandpa didn't say a single word.
It seems Haruki is in big trouble just for being a good friend. I hope Satsuki's dad is told feeding friends doesn't make you really more than friends yet. I've had that happen with mine before. Though of course we don't use each other's utensils.
It's not like it's an indirect kiss, you know?
Plus Satsuki really likes Haruki. Don't scare off Haruki, Satsuki's dad, you'll hurt Satsuki by doing that.