Kratos wasn't certain what sort of reaction he'd expected from Zeus, really. Probably more questions. But what he got was a kind of acceptance that he was in a good relationship. And maybe an admission that his king wasn't always happy with the way his own interactions with women went.
Or not, since he followed that up by saying relationships were not one-size-fits-all. That was actually a bit deeper than he'd anticipated, given the source. Or maybe it was just that in recent years Kratos had really ended up viewing his employer's attitudes towards women through the filter of his brother. He really couldn't recall having a conversation like this with Zeus before.
Lulled by the casual and intimate nature of the conversation they were having, Kratos blurted out without thinking, “Have you told Zelos that? Because I'm not sure he knows.”