@Sylveran, I think that Mambagi basically already does realize it. She's just hugely flustered at dealing with a guy who seems to be what he is. Unfortunately for her, he's effectively already taken.
The beginning gave me some advertisement vibes, with some characters getting craving for steak out of nowhere and someone conveniently knows the perfect place for it.
Wait... if this is the second time Agari has been there and she has a "marbled meat" Nicuca Card, does it mean that she ate...
*counts*
... 100 kg of meat in one sitting at the time of her first visit??