It's the librarian from Netflix's Hilda (a series based on a comic book by Luke Pearson). What do you mean by "my source"? Do you mean how do I know it's that character? Well... first, it just is her visually, and second, the same artist has made some previous pieces of her and put "librarian" on them (in japanese).
I'm not at all concerned with the show. I'm talking about where you located the image from. What website, post a link please. Twitter, tumblr? You need to go back and put a link to the post in the source field.