Lactis is one of the early Realian models, posted as a test model to the Federation Police 1875th Special Ops Command. Lactis had purple eyes, possibly due to his status as an early-model Realian. All other Realians have had yellow eyes. He had a somewhat melancholy personality.
He specialized in collecting and analyzing data for the U.M.N.; his responsibilities as a special forces member focused on those strengths. Furthermore, Lactis was one of the early-era Realians that had been installed with Program Canaan, a system thought up by Wilhelm as a way to detect people with a special "trait" (Shining Will) which would allow them to become a Testament. He is described by Wilhelm as carrying their "Canaan" and was used to find people with the "Essence".
As a result of Project Canaan's top secret development within Vector Industries, even its development process is unknown; absolutely no materials remain concerning it. Because the Program is built into the base system within the brain stem at the construction phase, even the Realian in question is unaware of its presence. It can be deduced that Lactis himself was unaware of the fact that he carried Program Canaan within his body.