I was Rejected 10,000 times by My Childhood Friend, but After I Gave Up, I Suddenly Started Getting Popular?

In the summer of my first year of elementary school, I confessed to my childhood friend, Karen, within two minutes of coming across her. Many years have passed since then, and I am now in my second year of high school. As of now, I’ve confessed my feelings to her 9999 times. Every time, I was rejected. But, I didn’t give up, and so I made this 10000th time my last chance to confess to Karen. “I’m sorry” she rejected me right away! I finally gave up and started trying to find a new love. But then, Karen started coming onto me, and I started to get popular?! What? Why? The mentally strongest high school student will be born here! Most of the characters are idiots, but they all go through their youth in their own clumsy ways.