Well, Gendo is definitely seen as an antagonist by this point. But Ritsuko was the flirtatious smart lady up until this point. And honestly, her flirting was m

Well, Gendo is definitely seen as an antagonist by this point. But Ritsuko was the flirtatious smart lady up until this point. And honestly, her flirting was mostly just trolling / fun. So I don't think anyone suspected the horrors of her designs until this scene.