If you feel any video is inappropriate in YouTube, you can report it using these steps: https://goo.gl/qVY8aM . Also, you can always manage your YouTube recommendations, tap the 3 dot menu > Not interested > Tell us why > I'm not interested in this channel.
don't you guys think ,that is inappropriate, there is a knife right through his stomach, and you said follow these step, my child watch this video, he accidentally click this video and watched he is six years old. do something.