Fabian grew up in Vienna, where he earned his undergraduate degree in law at the University of Vienna. Following graduation, he joined the Department of Private Law as a research and teaching assistant to the dean, Prof. Brigitta Zöchling-Jud, while simultaneously pursuing a PhD in law with a focus on private international law. His academic interests have taken him beyond Vienna: he attended the summer courses in private international law at The Hague Academy of International Law and conducted research as a visiting scholar at the Max Planck Institute for Comparative and International Private Law in Hamburg, Germany. Alongside his academic work, Fabian gained practical experience as an intern at the Austrian Constitutional Court and as a clerk at the Austrian Supreme Court.