I've seen this occur a lot online.
Sometimes it's people just trolling, but there are some people who really want people to think they drew something.
I have seen a lot of them on DeviantArt.
And to my surprise, they get reported, but still exist a year or so later.
It's so stupid.
I don't know if anyone has stolen my work.
I don't see why they would.
But I did have someone draw art of my OC, and I used it as my profile picture.
When I clicked on my account, I saw that a friend of a friend had the same image as their profile picture.
I panicked, and I told my friend, and we both messaged them to take it down because it was my OC, and art made for me only.
They apologized and changed it.
I don't mind things like that, but to knowingly take something you know you have no right to have...it pisses me off.
I actually drew a picture and posted it online, and someone said something like "Nice art. Who is it?" and I said "Just some random character." and they asked me if I even drew it.
I was like ">____> uh, yes."
Have you witnessed any art theft?