Lambda is a member of Shadow Garden, the secret organization founded by Cid Kagenou under his alias Shadow. She is assigned the number Lambda, corresponding to the eleventh letter of the Greek alphabet, and was formerly known as Zinaida before joining the group. She is a dark elf with white hair and golden eyes; she is frequently depicted with her right eye closed, a detail that suggests a past injury or loss of sight. As a former high-ranking military officer of the Vegalta Empire, Lambda brings extensive tactical knowledge and combat experience to Shadow Garden. Within the organization, she serves as the primary drill instructor and military adviser, responsible for training new recruits and overseeing their development. Her training methods are notably harsh and strict, a deliberate approach she believes is necessary to prepare the recruits for the dangerous missions they will face. Despite her severity during training, she is fair and acknowledges results when they are achieved, earning a degree of respect from those under her instruction.

Lambda’s background in the imperial military and her time as an intelligence officer have given her a deep understanding of the political and social dynamics of various nations, making her a valuable strategist. She is one of the few adult members of Shadow Garden, and Alpha, the leader of the Seven Shadows, occasionally seeks her counsel as a mature and experienced adviser. Lambda is fiercely loyal to Shadow and to the organization’s goal of destroying the Cult of Diablos, a cause she embraces fully after being rescued and empowered by Shadow’s magic. Her own combat abilities are formidable, honed by both her military past and the enhanced power granted by Shadow. She demonstrates exceptional control over the slime-based equipment used by Shadow Garden, capable of precision feats such as shredding a thin object like a food wrapper into fine powder.

In terms of key relationships, Lambda works closely with Alpha and the other Numbers, and she has a particularly strict dynamic with some of the more senior members, such as Epsilon, whom she has pushed hard during training sessions. Her role as an instructor also brings her into contact with newer recruits like Rose, whom she trains rigorously. While she can be feared for her demanding nature, Lambda’s dedication to the organization’s strength and her own quiet sense of duty make her a reliable and effective core member of Shadow Garden. Over the course of the story, she remains a steady presence in the background, focused on preparing the next generation of operatives and providing military guidance when needed.