You can save them.
You go to the drawer's profile and at "Latest Shared Creations", you press right mouse button and press "save image at..." and you select the place to save it on your computer.
(sorry if the english is bad, i'm catalan)
How do you save drawings to your computer
When you finish a drawing, click the Save Icon in the Top-right corner of the popup.
Erm,this game is very fun,but..how do i report people in it? -_-" somebody sent me a drawing of a penis and that wasn't even the answer,besides this game is rated E
That's just the reality of playing people on Newgrounds.
I found the troll face!