I finally realized the mistake because of that commotion, but I also realized it was already too late.

A short story, an SS. The protagonist is a foolish crown prince. In the end, he is outmaneuvered by his fiancée, whom he had thought was a villainess, and ends up having no choice but to rely on her. But somehow, compared to other noblemen, he comes out on top alone? Happiness with his fiancée, but he can no longer be trusted by her. Still, perhaps he receives some affection from her anyway? That's the kind of story this is. I am also posting this on Alphapolice.