Eva, add credit, please. You're a literal criminal.
Eva, you've done a lot of bad things, morally bad things, socially unacceptable things and legally upsetting and wrongful things.
Stealing people's artwork, whom they've spent a long time to compose, to refine, to perfect, is a crime against personal rights and legal rights. This is called copyright infringement and it's a nasty mark to get off your record. Not only is your reputation in jeopardy, but you'll be in some deep, hot and difficult legal troubles.
So, before you think that wrongfully taking a piece of art off someone, claiming it as yours, or editing it without proper credit and especially taking off their watermarks/branding/signatures, is nothing; think about how it'd feel and look to have someone steal something that YOU created and YOU took time to make, to design, to making with passion. It's not so different after all.
While we can't stop all art thieves, we can start person by person, and help them see the right way!
If you are against thievery of art, sign here, if you're against thievery in general, sign here, if you're scared of legal obligations because all of you are young people, then sign here!!