User blog comment:Miskos3/Fairy Tail Episode 251: Tartaros arc: A Young Boy's Story, Review/@comment-1359322-20150919103926/@comment-7418318-20150919121915

Well... Natsu's script is also barely legible, so it'd fit with his teachers.

But then... who did Erza ever learn to write from? She was captrued as a child, so I doubt her parents or school teachers were able to finish teaching her to write before she was taken.