User blog comment:Umbrello/Childhood Nightmares: TV/@comment-25987771-20150126170427/@comment-4849011-20150128011717

That character is named Kankuro (http://naruto.wikia.com/wiki/Kankur%C5%8D), and you were right to run out of the room when you did. Kankuro's opponent had been trying to break his neck, so after he got the upper hand he retaliated by breaking several of his bones. You didn't actually see Kankuro breaking his opponent's bones, but it was still disturbing because 1)Kankuro had made his intentions clear and 2)you could hear him screaming in pain.

There have been a lot of unsettling things in Naruto. In fact, Narutopedia had a thread a few months ago asking for the scariest things and characters in the series. I know a lot of it won't make sense to people who don't follow Naruto, but if anyone wants a look, here it is. http://naruto.wikia.com/wiki/Thread:135269