Annalise was confused by the question at first, but then she figured River was looking to have small talk with her since they were the only ones in the kitchen. When she was around River, she never got the chance to speak with him as much as she would like to because she would get so caught up with Beatrice.
Annalise wanted to know more about River since he had fought her father and he was the only person she ever heard her father complimented from this side. There were still petty insults here and there, but she could always tell from the way he spoke of River that he liked the challenge.
Her father would like a rematch since he claimed that he had gotten better and would now be able to take down the old knight. Annalise would rather he not fight River if there was ever a chance. One, because it would make things more complicated with Rafael, and two, he had more important issues to deal with than settling an old fight.