Anyways, bored at work so I thought I'd toss my two cents at the wall.
Welcome to the wall.

Let me just add a little legal guff, because I fell I need to say in a legal sense, the "non-kitschyness" of warhol's work really didn't determine if it was infringing or not.

(I should start using the word "kitsch" more. It is a good word.)
Legally, these are two different art pieces from two different artists:

You can read about Cariou vs. Prince case if you are as geeky about IP law as I tend to get.
Is called transformative vs derivative work. Simply put, you don't change enough and it is derivative work and is not entirely yours. You change enough and it is yours 100%, in an art ownership sense. The case above is one of those borderline cases, and normally transformative work has a bit more changed to it.
I feel comfortable saying that Gatsu's work is transformative. Gatsu legally owns that art and has every right to ask that guy to remove it.
There is a completely different issue on the IP on Scorpion himself, but it means nothing when selling the art by itself. Gatsu can sell the art, but he can't use any picture of Scorpion, even if drawn 100% himself, in order to profit selling on a video game, arcade machine, etc. That isn't the case in this incident, though.