|"Is this all real? Or has this been happening inside my head?"
The subject of this article is a real-life person, group, company, product, or creative work that has been mentioned "in-universe" in a canon source. The Harry Potter Wiki is written from the perspective that all information presented in canon is true (e.g., Hogwarts really exists), and, as such, details contained in this article may differ from real world facts.
Hermetray was an island in the Hebrides. After leaving Hogwarts School of Witchcraft and Wizardry out of protest at the young age of fourteen, Zygmunt Budge, considered an eccentric wizard, chose to live on this remote island. Here, he would conduct various potion experiments, eventually writing his masterwork Book of Potions.