Omega

One of the Numbers, a subordinate directly under Epsilon. A dark-skinned elf with tattoos on her right face and right half of her body, and heterochromatic eyes with the right one green and the left one yellow. Often acts in a pair with Kai, who is also directly under Epsilon.

In "Master of Garden," her past and the circumstances leading to her joining Shadow Garden are discussed.

Originally a high-ranking military officer in the Begalta Empire, her real name is Olga. She was a contemporary of Lambda and also served as an instructor. Unlike Lambda, who was patriotic, she had no loyalty to the empire and mechanically handled her duties. However, after becoming possessed by a demon, she was handed over to the Diabolos Cult and was being transported through the academic city of Lawagas when she was coincidentally rescued by Epsilon and others who were investigating Lawagas, leading to her joining Shadow Garden by chance. She later gained recognition for her abilities and achievements in operations within the Begalta Empire and became "Omega" of the Numbers.

In the TV anime version, her appearances significantly increase. She supports Kai, who uses a bicycle for human-powered electricity generation during his disguise as Jimina Senen, and in Season 2, Episode 8, she works alongside Kai as a shop clerk and performs various chores, including dubbing for videos.