Sodom functions as Luka Crosszeria's familiar. He manifests in three distinct forms: a black dragon, a powerful wolf-like creature, and a humanoid teenage boy. In this human form, he appears as a tanned youth with black hair, amber eyes, and distinctive cat ears. His typical attire includes a collar, detached sleeves, and occasionally opera gloves. Sodom exhibits a playful and affectionate demeanor, particularly toward Yuki Giou. He frequently expresses verbal declarations like "I love you, Yuki!" and seeks physical closeness, including climbing into Yuki's bed to snuggle, aiming to provide comfort and cheer. He demonstrates unwavering loyalty to Luka, obeying commands such as attacking Luze's familiar without hesitation. His personality incorporates energetic and impulsive traits, aligning with a "Keet" archetype. While primarily focused on Luka and Yuki, he maintains generally neutral or non-confrontational relationships with others unless Luka directs otherwise. Observers note moments where Luka quietly watches over Sodom during peaceful interactions, such as with a butterfly, suggesting mutual care within their master-familiar bond. Documented materials focus on his established role and traits without exploring an extensive background story, significant character development across extended media, or major changes in perspective.