My Teen Romantic Comedy: What did Yukinoshita mean "this will be the last one then you can end it."?
She says it because she believes that she was depending on hikigaya in every difficult situation. she knew that hikigaya was doing this (another prom) for her sake and to solve the problem and she thought she will rely on him for the last time as after the prom they will end the club which was their only way of communicating and she will go alone again and wouldn't have to rely on him again