You need to credit the art or reblog from the source. And delete any art edits that aren’t yours.

I do not try to steal anything, or any artwork. Well, I will write on my description that art in my blog are not my art and that credits goes to respective owners (because I have no idea of the sources, I have found these pictures randomly on google and social medias). If you are an artist and if you own any of the art on my blog though, please contact me and say what is the artwork I should remove. If not, then sorry but I will let them be on my blog. I believe, Tumblr is a place where you share what you like, I have seen a lot of people sharing what they like and edit what they like without any source, and they don’t delete it. I just want people to see what I like, there is no stealing intent there.