Is it weird for two girls to dance with each other? YoRHa is mainly comprised of female units, with the scanners being the odd ones out, so this isn't anything that 2B would be familiar with, thankfully for Rita.

2B turns her hand, pulling Rita's hand closer to lead her into a waltz, other hand lowering to the small of the other woman's back, though she doesn't quite move to start just yet.

"If you don't want to dance, you don't have to agree." There won't be any hurt feelings on 2B's part.

... There might be a little bit of hurt feelings on 2B's part, due to her innate programing, but unlike 9S, she'd hide it significantly better.