Tickle Torture: Bart Tickling Nelson

A pic I sketched up weeks ago and finally had time to go back and finish. It came out close to what I was imagining; Sadly, my scanner seems to be having issues so it's picking up erased lines and such in the pics, which means it's going to be replaced if it continues. Regardless, I was wanting to draw a Nelson/Bart pic for a while but didn't have a good concept of what the pic should look like. I think this is overdue, given how much Nelson picks on Bart. What do you think?