Male Trill who was the fifth host to the Dax symbiont. Torias was a test pilot who was joined about 2284 but lived less than a year thereafter. Torias married another joined Trill, a scientist named Nilani Kahn. Torias' career made Nilani nervous, and he accused her of panicking over nothing. But her worries were justified when Torias flew a shuttle that wasn't ready for a full impulse test. The shuttle crashed and Torias was critically injured. According to official Trill records, Torias was in a coma for just under six months, and doctors could not stabilize his isoboramine levels (isoboramine is a neurotransmitter that mediates synaptic functions between host and symbiont). When his levels fell below 40 percent of normal, they had to remove the symbiont, killing the host. Torias' death was recorded on Stardate 8615.2.

It was later discovered that the circumstances of Torias' death were altered in the official records. He was not in a coma for six months; rather, he had already died, and during that six months the Dax symbiont was joined with the murderous Joran Belar. The Trill Symbiosis Commission wished to cover up that fact for various reasons.

When Jadzia Dax, the eighth host, invoked the Trill Rite of Closure or "Zhian'tara" in 2371, she transferred the memories of Torias into her friend Julian Bashir. Despite a life cut short, Torias told Jadzia that he felt lucky to have been joined because he could continue to exist when the symbiont is passed to a new host.