Why Am I Like This

Killua had a horrible childhood which led to many mental problems that he would never admit to. What if one day all of it became too much for him to bear and he couldn't handle it anymore? What if he lost his composure in front of his friends? Would they leave him and call him weak or would they try to help him?
TW may contain mentions of panic attacks, abuse, strong violence, nightmares, and self harm if any of these things trigger you read at your own risk