Szule is apart of a race commonly referred to as Sirens - Or Spell-Singers, because of the fact their voices have a natural magical quality that is known to stupefy, entrance, or otherwise confuse anyone hearing their voice. No matter if they speak, yell or sing their voice may always sound the same to someone - soft and entrancing, silky and inviting, quiet and eerie, etc. Most Sirens, known simply as that in their own native tongue, will wear masks or decorative collars bearing an enchanted stone or sigil to otherwise 'filter the magic' out of their voices so they may interact with others without having adverse and uncontrollable effects.
Szule is apart of a Trio known among the Slave Trades as "The Fickle" which includes Tara Leif, Fetcher Auls, and Szule. Szule met Fetcher and Tara after they had already been interred in the slave trade for a few years, in which Szule met Fetcher in a near-death state simply from starvation and after learning what his main source of nourishment was - magic - Szule would sit and sing to Fetcher for hours on end until he was satiated and healthy. They formed their trio almost directly after that, realizing how badly they depended on each other and that they could always seek one another out when not interred under the grasp of a master.