Quote - I see that we can be neewbie in material room, render setting etc. but here we are experts ;)

  I certainly don't claim to be an expert, although I did get kicked out of Sunday School aged 7, for drawing a bottom. ( Yes honestly... but I think they overreacted a bit , it wasn't even a good drawing. ). Drawing that bottom didn't lead to a life of sordid porn, but doing it in Sunday school might have consigned me to en eternity in the fires of hell I suppose. I guess I will find out one day.

 "Is a knife dangerous? Do you give a knife to a 15 year old?"

I had a very sharp knife at 15, as sharp as a scalpel. I used it for model making. So far as I know I never took it outside the house, I had no reason to do so. I never thought of it as a weapon.