Aside the start with the semi-blackmail is a solid serie, hope we can learn to forgive and forget, even as the girl was just talking out her ass, true that a man hearing that kind of bullshit could get cold sweat and that explains how the MC is still grumpy about it.
In defense of the author it was a cliche for heroines to "blackmail" the MC his way for years in manga and anime, it just aged badly, like Bill Cosby or Subway Jared..
It will be all water under the bridge when they finally fuck.