Complex sentence: The story begins in Transylvania in the year 1450, Sonia Belmont, who in the game (not the series timeline) is the first Belmont to confront Dracula.
Split into simpler sentences: The story begins in Transylvania in the year 1450. In the game (although not the series's overall canon), Sonia Belmontvis the first Belmont to confront Dracula.