Lupin is a muscular man, dressed in a bodysuit resembling that of a superhero, with a belt, boots, and gloves. He also wears a cape, weathered at the edges. His most profound feature is his mask, that covers the top of his face, leaving his mouth and chin exposed. The mask also reveals glaring eyes and has two small ear-like or horn-like extensions on the back and a long sharp nose.
Thievery: Lupin is referred to as "phantom thief," suggesting he is immensely skilled in the art of theft.
Cornered by Death the Kid, Lupin witnesses in surprise as the Reaper's Demon Twin Guns transform into their respective human forms. As he watches Kid argue on the importance of symmetry after finding Patty out of the balanced alignment of their pose, he slips away in a hurry.
- Lupin's outfit, with its cape, horned mask, and superhero motif, has some resemblance to that of Charisma Justice, one of Atsushi Ōkubo's characters from his previous manga B. Ichi and who appears later in Soul Eater as one of Black☆Star's favorite comic book characters.