I generally don't flip if people re-post my stuff elsewhere on the Internet. Ideally I'd like to get credited, but that's why I try getting better with little watermarks on my stuff so I'll take care of that business my self... So if people just re-post some of my pics on places where that kinda thing isn't a direct violation, there's no need to contact me and let me know, UNLESS:
1. It's adult-rated works on a none-adult themed web site. Porn has no place on Facebook, Instagram, YouTube and other places like that! It's a violation of the sites' policy and if you see my adult stuff there, I'd be very happy if you report it and/or let me know of it so it can be removed from innocent eyes!
2. If the drawings has been edited in ANY way. Be it removal of my watermark/signature (note that my older pics do not have watermarks), slapping on other watermarks, slapping on horrid filters, changing colors, directly tracing it (I'm fine with referencing a bit), that kinda stuff. Also putting my art as preview on fics without permission. Very often the content of those fics are not in line with what the drawing is actually about and it basically "edits" the drawing! I very much appreciate being told about that kind of stuff taking place.
3. If the drawings have been posted on web sites that is specifically for content created by your self, like Deviant Art, Furaffinity and ect. Then re-posting will again be a direct violation of sites policies (unless permission has been granted) and should not by any stretch be there. Deviant Art is not 4Chan, learn the difference! And yes, let me know if my work pops up on art sites like this.
4. If someone directly tries stealing my identity/claiming my work as their own work! This is pretty serious shit and I'd VERY much appreciate being told if you see anyone do that!
These should be pretty obvious guidelines for most people on the subject in general. I know there are some that will disagree in either direction, but that's more opinion based.
PS. My Internet connection is very bad and I struggle to talk to folks online, so please have patience with me ><