Does Sano still think that she is the same naive girl that she once was? Surely not. Sumire knew that ever since that apology, he decided to stalk her. So he must understand by now that something like this would not work.
"Such cruel words. How could you say that after everything we have gone through? Are you going to abandon our relationship just like this? What about the promises you made?"
Wasnt he faltering? What suddenly made him regain his con-- Sumire paused when she noticed that a small crowd had gathered. It seems like he genuinely plans to corner her today. He could have done this last time, but Soujiro came.
Sano could easily turn this scenario into his favor and make her and Aika look like bad people.