I am not a native speaker. This usually comes as a surprise not only to people who have only known me by writing but also to people whose mother tongue actually is English and who met me in person. When I went to Canada for a holiday, most people assumed I was British. The Brits tended to think I was Australian for a while and nowadays just go by “you have an accent – but I have no idea what it is”. One of my Canadian friends even believed I was raised bilingually until I explained to him that no, I had started learning English when I was already eleven years old.
I lived in Edinburgh in 2010/2011 and did my masters degree there. It was probably the most amazing year of my life so far and it opened up so many new doors to me. I also met many lovely people from many different countries there whom I have done my best to stay in contact with.
Today, about fifty percent of my friends are international. Even though I live in Germany, at least half of my communication happens in English. I write fanfiction on the side and have done so for years. It never once crossed my mind to do that in German. I dream in English, I think in English and there’s literally no more effort involved in writing a story in English than there would be in writing one in German.
Considering the fact that almost everyone on this planet speaks English and hardly anyone speaks German, the choice which language “Prodigy” would be written in was pretty easy.