He's not especially frustrated, John is mostly still on the edges of being tense and uncomfortable. Talking about this is uncharted territory for him, and he's only managing it through the slowly descending fog of alcohol.

Still.

Once Ianto stalks talking about groping in the hallway and honey John rolls his eyes a little, winces.

"I was exaggerating a little for the audience," he says, "but I just --"

He trails off, takes a slow breath. He just wanted to do something wild to prove he wasn't afraid to touch Ianto, that he could be something like normal.

"Anyway, it's not you."

That's the key point. His eyes dart away uncomfortably again to some vague point that isn't looking at Ianto.