Sorry. If it wasn't just the pain from the vines (so they seem to be), it doesn't help that he's both infuriated and feeling his heart as it's wrung tight.

I would never— [hisses, he flinches again as the vines dig deeper] —give you the right to even consider me as family, you bitch.

[ Did Zero have his pistol drawn all this time? Because it sure suddenly seems like it, lifted point blank towards Ao. ]