Someone Help😩😩

So im thirteen and ive always been told i have a big butt. So this boy in my school always stares at me and always tries to ask me about having sex with him. And i always avoid it. But it hasnt been working cause he keeps asking. So should i just tell someone or should i just ignore it. Cause i have really low tolerance for this kinda stuff. And im known in my school for fighting people. And im really tempted to punch him in the face but i dont even kno anymore