anybody who wants to keep a decent image in a school
Think again, kid. Nobody cares whether a bunch of 12 year old little brats think you're a queer only because you have reported an incident that nearly killed you.
What do you suggest? Fight him? Do you think that a civil manner to resolve things? In fact, this is not going to only worsen his condition, as he could get seriously hurt; he may also not be capable of dealing with a situation where it is required large physical effort, such as a fight. It can also end up with a devastating outcome for both sides or even death.
Now, would you rather go through the risk of dying only to keep your image among a bunch of little brats or would you rather work your way in a civil and fair manner?