幼馴染（カノジョ）を親友に寝取られた俺。これからは元親友の妹とイチャイチャしていきたいと思います！ (Associated Names)

It’s only been three weeks since we started dating. And yet, I was cheated on. To make matters worse, the one she cheated with was my best friend. When I finally gathered my courage to kiss her, she told me that it was ‘too soon’. However, she just kissed him without a hint of hesitation.…