In DB it was just described as a language Harry didnt recognize. He was a Kemmler apprentice, but that doesnt mean he has to have european heritage, especially in his magic. He's described as having a Cultured accent, so paint him educated and he could reasonably have studied most any dead language, or even have bargained with something inhuman and learned magic in some non-human dialect, you know The Language of Blood (or somethign less cheezy
![Tongue :P](https://paranetonline.com/Smileys/default/tongue.gif)
). Id decide what flavor you plan to run with, and give him some obscure dead language from that region. Maybe he has a lot of aztec blood magic in his repitior, so he uses the language of the court shamen or some such.
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