Sym was a male human residing on the planet of Coruscant. He was a skilled historian of Coruscant, alongside his twin brother, Ellyt. In 230 BBY, while visiting Coruscant's clubs with friends Alees June and Loran, the twins encountered Amadeo Azzazzo, a Jedi Padawan. Azzazzo was then invited by June to join their group, and they proceeded to the Uzzu, a club where Sym placed his arm around his brother. Shortly after, they moved to an apartment with additional friends, where Azzazzo, prompted by Sym, displayed his lightsaber. Subsequently, the Jedi and June departed.
Both Sym and Ellyt were tall and slender, characterized by spiky, dark hair and black eyes. Sym's clothing was distinct, featuring a sleek combination of black, blue, and metallic hues, contrasting with Jedi robes worn by Azzazzo.
The short story "The Call of Coruscant," penned by Lydia Kang and featured in the 2023 young-adult anthology titled The High Republic: Tales of Light and Life, which is part of the Star Wars: The High Republic multimedia initiative, is where Sym made his appearance.