Lem, also called Lemnos, was a technician who knew Captain Hera Syndulla of the Spectres. In the early rebellion fighting against the Galactic Empire, Lemnos held a mechanic position at the Fekunda Outpost, reporting to Commander Zhou and his stormtrooper squad. His uniform consisted of grey overalls and a hat of the same color.
The character of Lemnos debuted in the third issue of the Star Wars: Forces of Destiny comic series. The comic didn't specify Lemnos's species, but Devin Grayson, the author, mentioned on social media that she envisioned him as a Selonian. However, Matt Martin from the Lucasfilm Story Group expressed a different opinion, doubting that Lemnos was intended to be a Selonian when questioned.